[llvm] Revert "[AMDGPU] SelectionDAG divergence tracking should take into account Target divergency. (#147560)" (PR #152548)

[David Stuttard via llvm-commits]

dstutt wrote:

> You don't need a PR to revert a commit. Instead, you can directly revert it locally and push it to main. Please include the reason for the revert.

I did this as a PR as the revert was not that straight-forward, but I guess I should have said that in the comment.

https://github.com/llvm/llvm-project/pull/152548