[llvm] [Intrinsics][AArch64] Add intrinsic to mask off aliasing vector lanes (PR #117007)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

Could you update the description to reflect the current state of the PR?

>From the current description it is also not clear why we need different intrinsics for write-after-read and read-after-write. Would be great if you could add a brief explanation to the description as well

https://github.com/llvm/llvm-project/pull/117007