[llvm] [LoopSplitUtils] Revert, removing from tree (PR #214577)

[Ramkumar Ramachandra via llvm-commits]

artagnon wrote:

@fhahn Can we kindly get this revert landed, so that @nema-ashutosh can start working on a re-land?

https://github.com/llvm/llvm-project/pull/214577