Share inline(never) generics across crates

This reduces code sizes and better respects programmer intent when
marking inline(never). Previously such a marking was essentially ignored
for generic functions, as we'd still inline them in remote crates.

library/std/src/lib.rs

@@ -362,6 +362,7 @@
 #![feature(strict_provenance_atomic_ptr)]
 #![feature(sync_unsafe_cell)]
 #![feature(ub_checks)]
+#![feature(used_with_arg)]
 // tidy-alphabetical-end
 //
 // Library features (alloc):