[llvm] [LLVM][InstCombine][AArch64] Refactor common SVE intrinsic combines. (PR #126928)

[David Sherwood via llvm-commits]

https://github.com/david-arm commented:

Phew, took a while to double check consistency of all the intrinsics. :) It looks good though. I just had a couple of minor questions ...

https://github.com/llvm/llvm-project/pull/126928