Rollup merge of #155131 - sorairolake:stabilize-uint-bit-width, r=jhpratt

Stabilize feature `uint_bit_width`

Tracking issue: rust-lang/rust#142326
FCP is finished in rust-lang/rust#142326 (comment)

Closes rust-lang/rust#142326

@rustbot modify labels: +T-libs-api

Author: JonathanBrouwer