[llvm] [AMDGPU] Enable "amdgpu-uniform-intrinsic-combine" pass in pipeline. (PR #162819)

[Pankaj Dwivedi via llvm-commits]

PankajDwivedi-25 wrote:

> LGTM. Code formatting has failed in CI. Could merge after fixing it.

There is no `undef` present as such in the IR test, it appears in checks generated.

https://github.com/llvm/llvm-project/pull/162819