[llvm] [AArch64][SVE] - Fix crash Possible incorrect use of EVT::getVectorNumElements(). (PR #218733)

[David Sherwood via llvm-commits]

david-arm wrote:

> I think the correct fix here is to use ElementCount and handle scalable vectors

I'm not sure how feasible that is because the code below demands the known bits, which might not work for scalable types.

https://github.com/llvm/llvm-project/pull/218733