[clang] [llvm] [AMDGPU] Add an option to disable unsafe uses of atomic xor (PR #69229)

[Pierre-Andre Saulais via cfe-commits]

pasaulais wrote:

Also, this will need to be extended to other operations that can be impacted by fine-grained and remote access like `add`, `and`, `or`, `sub`, `fpadd` and `fpsub`.

https://github.com/llvm/llvm-project/pull/69229