[llvm] [AArch64][SVE2] Lower OR to SLI/SRI (PR #77555)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

I happened to have a patch a while back to change the And in tryLowerToSLI to use KnownBits. It was causing some issues in the tests though, and should be mutually exclusive to this. It just might help it trigger in more cases.

The patch here looks good, from what I can tell.

https://github.com/llvm/llvm-project/pull/77555