[llvm] [SCCP] Handle llvm.experimental.get.vector.length calls (PR #169527)

[Luke Lau via llvm-commits]

================

----------------
lukel97 wrote:

We can't handle vscale/get.vector.length in ConstantRange::intrinsic because we need to access the Function. In a follow up we could plumb through the Function and move the two intrinsics in there?

https://github.com/llvm/llvm-project/pull/169527