[llvm] [TableGen] Fix validateOperandClass for non Phyical Reg (PR #118146)

[Jay Foad via llvm-commits]

jayfoad wrote:

> > Can you add a test case for this?
> 
> Sorry, I don't see easy way to do so, it involves defining a new target

Well, OK, but with no test and no in-tree use there is nothing to stop your use case being broken again in future. Did you consider just carrying the tablegen change downstream?

https://github.com/llvm/llvm-project/pull/118146