[llvm] Update amdgpu_gfx functions to use s0-s3 for inreg SGPR arguments on targets using scratch instructions for stack (PR #78553)

[Rajveer Singh Bharadwaj via llvm-commits]

Rajveer100 wrote:

Do I have to include any additional builds (like _openmp_) in the llvm build to generate those tests, as they are currently only in the _llvm/_ directory and hence isn't invoked by _update_llc_test_checks_ due to this.

https://github.com/llvm/llvm-project/pull/78553