[clang] [Clang][Sema] Implement approved resolution for CWG2858 (PR #88042)

[Vlad Serebrennikov via cfe-commits]

Endilll wrote:

`make_cxx_dr_status` is not going to do anything here, since the DR indeed didn't make it into public list.
Merge as-is. 2858 is going to be picked up when someone runs the script for the first time after a new revision of core issues list is published.

https://github.com/llvm/llvm-project/pull/88042