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

[via cfe-commits]

https://github.com/cor3ntin commented:

The `__cpp_sized_deallocation`  feature test macro should be set to 201309L

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