[llvm] [IA] Support vp.load in lowerInterleavedLoad [nfc-ish] (PR #149174)

[Philip Reames via llvm-commits]

preames wrote:

> > So this adds the ability to form a strided load for a vp.load deinterleave with one shuffle used.
> 
> Do you want to add a test for this?

Done, see vp_load_factor3_one_active and vp_load_factor5_one_active in the most recent merge.

https://github.com/llvm/llvm-project/pull/149174