[polly] [Polly] Isolate complete tiles from partial tiles in the tiling path (PR #221087)

[Michael Kruse via llvm-commits]

Meinersbur wrote:

I forgot something: Can you add an item to the release notes (https://github.com/llvm/llvm-project/blob/main/polly/docs/ReleaseNotes.rst)? That should be done for any behavioral changes that are not just a bugfix.

https://github.com/llvm/llvm-project/pull/221087