aco: Don't use vcmpx with DPP.
According to the ISA docs the behavior may be unexpected when exec isn't -1.
Fixes: baab6f18 ("aco: Optimize branching sequence during SSA elimination.")
According to the ISA docs the behavior may be unexpected when exec isn't -1.
Fixes: baab6f18 ("aco: Optimize branching sequence during SSA elimination.")