[clang] [llvm] [C++23] [CLANG] Adding C++23 constexpr math functions: fmin, fmax and frexp. (PR #88978)

[Zahira Ammarguellat via cfe-commits]

zahiraam wrote:

> > All the LIT tests failing are due to the latest changes I made. I will edit them once I know that the latest implementation is correct.
> 
> Thanks. I may be delayed in reviewing this as the C++ committee meeting is the week after next.

Ping @hubert-reinterpretcast 

https://github.com/llvm/llvm-project/pull/88978