Auto merge of rust-lang#87980 - Manishearth:rollup-vkuix3y, r=Manishearth

Rollup of 4 pull requests

Successful merges:

 - rust-lang#87916 (Implement `black_box` using intrinsic)
 - rust-lang#87922 (Add c_enum_min_bits target spec field, use for arm-none and thumb-none targets)
 - rust-lang#87953 (Improve formatting of closure capture migration suggestion for multi-line closures.)
 - rust-lang#87965 (Silence non_fmt_panic from external macros.)

Failed merges:

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

Author: bors