[llvm] [AMDGPU] Avoid setting GLC for image atomics when result is unused (PR #150742)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> I think we may need a new intrinsic? For example, I’ve already implemented a draft that lowers:

No, do not add a new intrinsic. Rely purely on use_empty of the result


https://github.com/llvm/llvm-project/pull/150742