Shorten span of panic failures in const context

Previously, we included a redundant prefix on the panic message and a postfix of the location of the panic. The prefix didn't carry any additional information beyond "something failed", and the location of the panic is redundant with the diagnostic's span, which gets printed out even if its code is not shown.

```
error[E0080]: evaluation of constant value failed
  --> $DIR/assert-type-intrinsics.rs:11:9
   |
LL |         MaybeUninit::<!>::uninit().assume_init();
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ aborted execution: attempted to instantiate uninhabited type `!`
```

```
  --> $DIR/collect-in-dead-closure.rs:9:19
   |
LL |     const C: () = panic!();
   |                   ^^^^^^^^ explicit panic
   |
   = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
```
```
error[E0080]: evaluation of constant value failed
  --> $DIR/uninhabited.rs:87:9
   |
LL |         assert!(false);
   |         ^^^^^^^^^^^^^^ assertion failed: false
   |
   = note: this error originates in the macro `assert` (in Nightly builds, run with -Z macro-backtrace for more info)
```

Author: estebank

compiler/rustc_const_eval/messages.ftl

@@ -298,8 +298,7 @@ const_eval_overflow_arith =
 const_eval_overflow_shift =
     overflowing shift by {$shift_amount} in `{$intrinsic}`
 
-const_eval_panic =
-    the evaluated program panicked at '{$msg}', {$file}:{$line}:{$col}
+const_eval_panic = {$msg}
 
 const_eval_panic_non_str = argument to `panic!()` in a const context must have type `&str`
 

compiler/rustc_const_eval/src/const_eval/error.rs

@@ -48,11 +48,8 @@ impl MachineStopType for ConstEvalErrKind {
             | ModifiedGlobal
             | WriteThroughImmutablePointer => {}
             AssertFailure(kind) => kind.add_args(adder),
-            Panic { msg, line, col, file } => {
+            Panic { msg, .. } => {
                 adder("msg".into(), msg.into_diag_arg());
-                adder("file".into(), file.into_diag_arg());
-                adder("line".into(), line.into_diag_arg());
-                adder("col".into(), col.into_diag_arg());
             }
         }
     }

src/tools/miri/tests/fail/erroneous_const.stderr

@@ -2,7 +2,7 @@ error[E0080]: evaluation of `PrintName::<i32>::VOID` failed
   --> tests/fail/erroneous_const.rs:LL:CC
    |
 LL |     const VOID: ! = panic!();
-   |                     ^^^^^^^^ the evaluated program panicked at 'explicit panic', tests/fail/erroneous_const.rs:LL:CC
+   |                     ^^^^^^^^ explicit panic
    |
    = note: this error originates in the macro `$crate::panic::panic_2021` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
 

tests/ui/borrowck/issue-81899.stderr

@@ -2,7 +2,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/issue-81899.rs:11:5
    |
 LL |     panic!()
-   |     ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/issue-81899.rs:11:5
+   |     ^^^^^^^^ explicit panic
    |
 note: inside `f::<{closure@$DIR/issue-81899.rs:4:31: 4:34}>`
   --> $DIR/issue-81899.rs:11:5

tests/ui/borrowck/issue-88434-minimal-example.stderr

@@ -2,7 +2,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/issue-88434-minimal-example.rs:10:5
    |
 LL |     panic!()
-   |     ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/issue-88434-minimal-example.rs:10:5
+   |     ^^^^^^^^ explicit panic
    |
 note: inside `f::<{closure@$DIR/issue-88434-minimal-example.rs:3:25: 3:28}>`
   --> $DIR/issue-88434-minimal-example.rs:10:5

tests/ui/borrowck/issue-88434-removal-index-should-be-less.stderr

@@ -2,7 +2,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5
    |
 LL |     panic!()
-   |     ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/issue-88434-removal-index-should-be-less.rs:10:5
+   |     ^^^^^^^^ explicit panic
    |
 note: inside `f::<{closure@$DIR/issue-88434-removal-index-should-be-less.rs:3:31: 3:34}>`
   --> $DIR/issue-88434-removal-index-should-be-less.rs:10:5

tests/ui/coherence/const-errs-dont-conflict-103369.stderr

@@ -2,7 +2,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/const-errs-dont-conflict-103369.rs:10:5
    |
 LL |     panic!("Some error occurred");
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'Some error occurred', $DIR/const-errs-dont-conflict-103369.rs:10:5
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Some error occurred
    |
 note: inside `my_fn`
   --> $DIR/const-errs-dont-conflict-103369.rs:10:5
@@ -20,7 +20,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/const-errs-dont-conflict-103369.rs:10:5
    |
 LL |     panic!("Some error occurred");
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'Some error occurred', $DIR/const-errs-dont-conflict-103369.rs:10:5
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Some error occurred
    |
 note: inside `my_fn`
   --> $DIR/const-errs-dont-conflict-103369.rs:10:5

tests/ui/const-ptr/forbidden_slices.stderr

@@ -102,7 +102,7 @@ LL | pub static R0: &[u32] = unsafe { from_ptr_range(ptr::null()..ptr::null()) }
 error[E0080]: could not evaluate static initializer
   --> $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
-   = note: the evaluated program panicked at 'assertion failed: 0 < pointee_size && pointee_size <= isize::MAX as usize', $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
+   = note: assertion failed: 0 < pointee_size && pointee_size <= isize::MAX as usize
    |
 note: inside `std::ptr::const_ptr::<impl *const ()>::sub_ptr`
   --> $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL

tests/ui/consts/assert-type-intrinsics.stderr

@@ -2,19 +2,19 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/assert-type-intrinsics.rs:11:9
    |
 LL |         MaybeUninit::<!>::uninit().assume_init();
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'aborted execution: attempted to instantiate uninhabited type `!`', $DIR/assert-type-intrinsics.rs:11:36
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ aborted execution: attempted to instantiate uninhabited type `!`
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/assert-type-intrinsics.rs:15:9
    |
 LL |         intrinsics::assert_mem_uninitialized_valid::<&'static i32>();
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'aborted execution: attempted to leave type `&i32` uninitialized, which is invalid', $DIR/assert-type-intrinsics.rs:15:9
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ aborted execution: attempted to leave type `&i32` uninitialized, which is invalid
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/assert-type-intrinsics.rs:19:9
    |
 LL |         intrinsics::assert_zero_valid::<&'static i32>();
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'aborted execution: attempted to zero-initialize type `&i32`, which is invalid', $DIR/assert-type-intrinsics.rs:19:9
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ aborted execution: attempted to zero-initialize type `&i32`, which is invalid
 
 error: aborting due to 3 previous errors
 

tests/ui/consts/const-eval/const_panic-normalize-tabs-115498.stderr

@@ -2,7 +2,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/const_panic-normalize-tabs-115498.rs:3:17
    |
 LL | struct Bug([u8; panic!{"\t"}]);
-   |                 ^^^^^^^^^^^^ the evaluated program panicked at '    ', $DIR/const_panic-normalize-tabs-115498.rs:3:17
+   |                 ^^^^^^^^^^^^     
    |
    = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)