[clang] [clang-tools-extra] [libcxx] Reland "[clang] Enable sized deallocation by default in C++14 onwards" (PR #90373)

[Pengcheng Wang via cfe-commits]

wangpc-pp wrote:

Please review this PR as all noticable issues have been fixed I think.

https://github.com/llvm/llvm-project/pull/90373