[llvm] LAA: rearrange in preparation to scale strides (NFC) (PR #122113)

[David Sherwood via llvm-commits]

https://github.com/david-arm approved this pull request.

LGTM! It might be good to amend the title to something like "LAA: Refactor dependence classes in preparation for scaled strides (NFC)"

https://github.com/llvm/llvm-project/pull/122113