[llvm] [AMDGPU][GFX11] Add more test coverage for FMA instructions. (PR #65935)

[Ivan Kosarev via llvm-commits]

kosarev wrote:

> > Commit [79f52af](https://github.com/llvm/llvm-project/commit/79f52af4cd9a76485dd50bcdbb5d393eb7a70103) fixed the problem.
> This commit is from Nov 8, 2021. Maybe you linked the wrong one?

Yep, that the one that was fixed by it, not the fix itself. Updated, thanks.

https://github.com/llvm/llvm-project/pull/65935