Auto merge of #97435 - Patryk27:bump-compiler-builtins, r=Dylan-DPC

library/std: Bump compiler_builtins

Some neat changes include faster float conversions & fixes for AVR 🙂

(note that's it's my first time upgrading `compiler_builtins`, so I'm not 100% sure if bumping `library/std/Cargo.toml` is enough; certainly seems to be so, though.)

Author: bors