[libc][c23] add definitions for stdckdint.h (#82059)

See docs at
- https://gustedt.gitlabpages.inria.fr/c23-library/#stdckdint
- https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3047.pdf (Ch7.10)

Compiler header:
-
https://github.com/llvm/llvm-project/blob/450462cbaceddf57812ce15b5135b17f65a77654/clang/lib/Headers/stdckdint.h
- New version of GCC
(https://github.com/gcc-mirror/gcc/blob/cd503b0616462445381a8232fb753239d319af76/gcc/ginclude/stdckdint.h)
also provides this.