Previously, any associated function could have `~const` trait bounds on
generic parameters, which could lead to ICEs when these bounds were used
on associated functions of non-`#[const_trait] trait` or
non-`impl const` blocks.

Includes changes as per @fee1-dead's comments in rust-lang#116210.

…-check, r=davidtwco

Add check_unused_messages in tidy

From rust-lang#115728 (comment)
The check is not 100% accurate, I guess it's enough for now.

Ensure that `~const` trait bounds on associated functions are in const traits or impls

Zulip discussion: https://rust-lang.zulipchat.com/#narrow/stream/146212-t-compiler.2Fconst-eval/topic/How.20to.2Fshould.20I.20try.20to.20pinpoint.20ICEs.20related.20to.20effects.3F

Rename both of the `Match` relations

Both of these names kinda were ambiguous.

r? lcnr

Remove unused features from `rustc_llvm`.

r? `@bjorn3`

Print normalized ty

Inside `mir_assign_valid_types` we are comparing normalized type of `mir_place` but in debug message we are not printing the normalized value, this changes that.