[llvm] [AMDGPU] Insert readfirstlane in the function returns in sgpr. (PR #135326)

[Jan Patrick Lehr via llvm-commits]

jplehr wrote:

This broke a couple of our bots.
E.g. https://lab.llvm.org/buildbot/#/builders/10/builds/3849

They were red due to prior fails, so did not comment here.

https://github.com/llvm/llvm-project/pull/135326