add std.hash.uint32

This is handy if you have a u32 and want a u32 and don't want to take a
detour through many layers of abstraction elsewhere in the std.hash
namespace.
Copied from https://nullprogram.com/blog/2018/07/31/
1c7095cb7dAndrew Kelley committed on 6/11/2023, 3:42:30 AMparent3ba099b
1 file changedLine totals unavailable