[Bug libstdc++/88322] Implement C++20 library features.

[emsr at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88322
Bug 88322 depends on bug 89022, which changed state.

Bug 89022 Summary: Implement P0202R3 - C++20 Constexpr Modifiers to Functions 
in <algorithm> and <utility> Headers.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89022

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED