Remove __probestack stub

This bug has been fixed upstream in the latest compiler-builtins crate.

Author: GabrielMajeri

uefi-test-runner/src/main.rs

@@ -17,9 +17,6 @@ use uefi::table::boot::MemoryDescriptor;
 mod boot;
 mod proto;
 
-#[no_mangle]
-extern "C" fn __rust_probestack() {}
-
 #[entry]
 fn efi_main(image: Handle, st: SystemTable<Boot>) -> Status {
     // Initialize utilities (logging, memory allocation...)