[llvm] AMDGPU: Propagate amdgpu-max-num-workgroups attribute (PR #113018)

[Shilei Tian via llvm-commits]

shiltian wrote:

Half-baked values are no longer added. That is expected. If all call sites of a function are clear, then it should work.

https://github.com/llvm/llvm-project/pull/113018