[clang] [llvm] Reland "[LLVM] Add IRNormalizer Pass" (PR #113780)

[Justin Fargnoli via cfe-commits]

justinfargnoli wrote:

> Is it possible/easy to split https://github.com/llvm/llvm-project/commit/ef6a751a794c3e2d266cac0242629043ddd0d2aa into a new PR?

Certainly, @boomanaiden154! Please see #116108 :)

https://github.com/llvm/llvm-project/pull/113780