[llvm] [llvm] include GenericLoopInfoImpl for full implementation (PR #144621)

[Saleem Abdulrasool via llvm-commits]

https://github.com/compnerd approved this pull request.

I think that this is fine, but, we should file an issue that clang-cl diverges from cl here.

https://github.com/llvm/llvm-project/pull/144621