[llvm] [MemoryLocation] Teach MemoryLocation about llvm.experimental.memset.pattern (PR #120421)

[Alex Bradbury via llvm-commits]

asb wrote:

> > Stacks on top of #120420.
> 
> I don't see any obvious dependency on this. Why not separate this out so it can go in independently of that one?

You're right, that would make more sense. As I don't have a good way of removing the dependency other than rebasing, I've removed the dependency and force pushed. I've updated the description to reflect this change.

https://github.com/llvm/llvm-project/pull/120421