[llvm] [GlobalOpt] Handle operators separately when removing GV users (PR #84694)

[Anshil Gandhi via llvm-commits]

gandhi56 wrote:

I might be able to merge the `cleanupPointerRootUsers` and `cleanupConstantGlobalUsers` if I perform checks properly. I will work on that and update this PR.

https://github.com/llvm/llvm-project/pull/84694