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

[Mark de Wever via cfe-commits]

https://github.com/mordante commented:

I only looked at the libc++ changes and have some minor comments to update this patch to the latest libc++ style.

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