[llvm] [polly] [IR] Enable dereferenceable-at-point semantics (PR #204795)

[Danila Malyutin via llvm-commits]

danilaml wrote:

@nikic what about LLVM intrinsics? Don't see memcpy/memset and co marked as nofree.

https://github.com/llvm/llvm-project/pull/204795