[llvm] [LoadStoreVectorizer] Propagate alignment through contiguous chain (PR #145733)

[Drew Kersnar via llvm-commits]

dakersnar wrote:

Adding @michalpaszkowski to reviewers since I saw you reviewed a recently merged LSV change. If you can think of anyone else who would be a better fit to review this let me know :)

https://github.com/llvm/llvm-project/pull/145733