Rollup of 16 pull requests

Successful merges:

 - #137494 (libstd: init(): dup() subsequent /dev/nulls instead of opening them again)
 - #144541 (c-variadic: multiple ABIs in the same program for arm)
 - #144613 (aarch64-nintendo-switch-freestanding - Enable CPU features that are always available in a live system (crypto instructions, plus explicit NEON).)
 - #144780 (Add a method to dump MIR in the middle of MIR building)
 - #145137 (Consolidate panicking functions in `slice/index.rs`)
 - #145507 (Refactor attribute parsing to improve ergonomics and some diagnostics)
 - #145604 (Gate static closures behind a parser feature)
 - #145648 (Add two tidy dependency checks)
 - #145661 (update some s390x codegen tests)
 - #145672 (Instantiate higher-ranked binder with erased when checking `IntoIterator` predicate for query instability)
 - #145689 (Migrate `panic_unwind` to use `cfg_select!`)
 - #145700 (Handle `ReEarlyParam` in `type_name`.)
 - #145703 (Remove MIPS targets from CI LLVM platforms)
 - #145704 (ci: don't cleanup windows disk)
 - #145705 (remove an `as` cast in prefetch codegen)
 - #145712 (Update outdated link in bound region comments)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of #145703 - Gelbpunkt:ci-llvm-mips, r=Kobzol

Remove MIPS targets from CI LLVM platforms

All of these were demoted to tier 3 a while ago and we aren't building LLVM for them anymore.