[clang] [llvm] [LoongArch] Add `-fstack-clash-protection` support (PR #195595)

[Jan Svoboda via cfe-commits]

https://github.com/jansvoboda11 commented:

The Clang part LGTM, but of course wait for the LLVM part to get approved as well.

https://github.com/llvm/llvm-project/pull/195595