Auto merge of #101514 - nvzqz:nvzqz/stabilize-nonzero-bits, r=thomcc

Stabilize `nonzero_bits`

Closes #94881, implemented by #93292.

This change stabilizes the associated `BITS` constant for `NonZero{U,I}{8,16,32,64,128,size}` integers, e.g.:

```rs
impl NonZeroUsize {
    pub const BITS: u32 = usize::BITS;
}
```

Author: bors