[llvm] [AMDGPU][wmma] - Add tied wmma intrinsic (PR #69903)

[Jay Foad via llvm-commits]

jayfoad wrote:

> > The "Simplify wmma instruction defs" commit is clearly good. Maybe commit that one separately first?
> 
> Did that in [this PR](https://github.com/llvm/llvm-project/pull/70622). Closing this PR for now. I will open another one for the new intrinsics after that one is merged.

I think it would have been fine to leave this one open it and rebase it after that one was merged. I know some people don't like force pushing because it loses some context, but it's surely better than closing the PR and opening a new one which loses _all_ context.

https://github.com/llvm/llvm-project/pull/69903