[polly] [polly] Port polly tests to use NPM (PR #90632)

[Arthur Eubanks via llvm-commits]

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

I obviously didn't look through every file, but seems right to me

please mention in the commit description that you've replaced the `%loadPolly` lit substitution with the previous `%loadNPMPolly` and removed `%loadNPMPolly`

https://github.com/llvm/llvm-project/pull/90632