[llvm] [Delinearization] Remove tryDelinearizeFixedSizeImpl (PR #169046)

[Sjoerd Meijer via llvm-commits]

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

Thanks, LGTM

@sebpop pointed one thing out to me offline: maybe Polly test cases need fixing up.
@Meinersbur: what is the policy around this? Should that be part of this patch? Or done separately?

https://github.com/llvm/llvm-project/pull/169046