[llvm] [AMDGPU] Suppress DataLayout warnings after recent change (PR #163644)

[Joseph Huber via llvm-commits]

jhuber6 wrote:

> I'm not sure if we can do this in IR auto upgrade instead of suppressing the warning?

IR Linker auto upgrades are currently applied after this check I believe, but I suppose we could add one beforehand? Not sure if that's correct either because it is a legitimately different data layout with different semantics. This mostly just suppresses the warning because there's nothing the user can do about it and it's unreasonable for an empty `.cpp` file to fill the entire screen with warnings.

https://github.com/llvm/llvm-project/pull/163644