[llvm] [LoopVectorize] Refine runtime memory check costs when there is an outer loop (PR #76034)

[David Sherwood via llvm-commits]

david-arm wrote:

Hi @fhahn, ok thanks. It wasn't obvious to me that those cases were checking for outer loops, so thanks for pointing them out! I've changed them now.

https://github.com/llvm/llvm-project/pull/76034