[llvm] [AMDGPU] Swap V_CNDMASK operands to shrink it into VOP2 (PR #135162)

[Mirko Brkušanin via llvm-commits]

mbrkusanin wrote:

> > * Needs rebase
> > * Please add tests for a negative case, case with source modifiers and when shouldSwapCndOperands counter is positive.
> 
> should this be added for all compare kinds?

No, just one is enough.

https://github.com/llvm/llvm-project/pull/135162