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

[Rong Mantle Bao via llvm-commits]

CSharperMantle wrote:

@wangleiat: If v3 looks good to you, would you mind helping me to merge it (after your approval, of course)? Many thanks.

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