[clang] [llvm] [mlir] [AMDGPU] Fix missing cache bypass scope on seq_cst buffer fat pointer atomics (PR #213585)

[Arseniy Obolenskiy via cfe-commits]

aobolensk wrote:

Probably, it should be simplified anyhow, but clang and mlir changes are still required to be together here

https://github.com/llvm/llvm-project/pull/213585