[llvm] [AMDGCN][SIWholeQuadMode] Handle case when SI_KILL_I1_TERMINATOR -1,0 is not the only terminator (PR #122922)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> or even at IR level.

We could do this if we started using / requiring using callbr for this intrinsic (which is something we should do). But I would expect this to have folded out before this point 



https://github.com/llvm/llvm-project/pull/122922