[clang] [clang-tools-extra] [libcxx] [clang] Enable sized deallocation by default in C++14 onwards (PR #83774)

[Vlad Serebrennikov via cfe-commits]

https://github.com/Endilll approved this pull request.

I used a different approach for CWG292 test that avoids passing `-fsized-deallocation` in 98 and 11 modes, as this is not a conforming mode for them. Now changes to DR tests look good :) I hope you don't mind me pushing commits to your PR.

(I'm the author of CWG292 test)

https://github.com/llvm/llvm-project/pull/83774