[llvm] [AArch64][ARM] Optimize more `tbl`/`tbx` calls into `shufflevector` (PR #169748)

[David Green via llvm-commits]

davemgreen wrote:

Sounds like they should request access :)

@valadaptive are you happy for this to go in? Does the commit message need any cleanup?

https://github.com/llvm/llvm-project/pull/169748