[llvm] [AArch64] Add SVE patterns for [su]adalp with separate ADD. (PR #204796)

[Paul Walker via llvm-commits]

https://github.com/paulwalker-arm requested changes to this pull request.

Please can you implement this as an InstCombine (or a DAGCombine if that's not possible) instead?

https://github.com/llvm/llvm-project/pull/204796