[llvm] [DA] Fix the check between Subscript and Size after delinearization (PR #151326)

[Ryotaro Kasuga via llvm-commits]

https://github.com/kasuga-fj commented:

> There are many remaining issues with DA, but let's improve it step-by-step.

Thank you, that really encourages me.

https://github.com/llvm/llvm-project/pull/151326