[llvm] Revert "[AMDGPU] Re-apply: Implement vop3p complex pattern optmization for gisel" (PR #146982)

[Shilei Tian via llvm-commits]

shiltian wrote:

You can directly revert it locally and push the change w/o creating a PR. Merging a PR w/o review is discouraged IIUC.

https://github.com/llvm/llvm-project/pull/146982