Rollup merge of rust-lang#80404 - JulianKnodt:arr_ref, r=oli-obk

Remove const_in_array_repeat

Fixes rust-lang#80371. Fixes rust-lang#81315. Fixes rust-lang#80767. Fixes rust-lang#75682.

I thought there might be some issue with `Repeats(_, 0)`, but if you increase the items in the array it still ICEs. I'm not sure if this is the best fix but it does fix the given issue.

Author: jonas-schievink

alloc/src/lib.rs

@@ -89,7 +89,6 @@
 #![feature(coerce_unsized)]
 #![feature(const_btree_new)]
 #![feature(const_fn)]
-#![feature(const_in_array_repeat_expressions)]
 #![feature(cow_is_borrowed)]
 #![feature(const_cow_is_borrowed)]
 #![feature(dispatch_from_dyn)]