[polly] [Polly] Data flow reduction detection to cover more cases (PR #84901)

[Karthika Devi C via llvm-commits]

kartcq wrote:

Thanks @Meinersbur and @efriedma-quic for your time to review and approvals.
I have addressed all the final comments as well.
With the builders passing this patch is good to go for merging.

https://github.com/llvm/llvm-project/pull/84901