[AMDGPU] Fixed incorrect test in vcnd/vcmp optimization

This fixes a test I introduced in change D59191 (that added src0 and
src1 modifiers to the v_cndmask instruction for disassembly purposes).

Spotted by David Binderman in bug 41488.

Differential Revision: https://reviews.llvm.org/D60652

Change-Id: I6ac95e66cd84e812ed3359ad57bcd0e13198ba0c
llvm-svn: 358392

llvm/lib/Target/AMDGPU/SIOptimizeExecMaskingPreRA.cpp

@@ -223,7 +223,7 @@ static unsigned optimizeVcndVcmpPair(MachineBasicBlock &MBB,
     return AMDGPU::NoRegister;
 
   if (TII->hasModifiersSet(*Sel, AMDGPU::OpName::src0_modifiers) ||
-      TII->hasModifiersSet(*Sel, AMDGPU::OpName::src0_modifiers))
+      TII->hasModifiersSet(*Sel, AMDGPU::OpName::src1_modifiers))
     return AMDGPU::NoRegister;
 
   Op1 = TII->getNamedOperand(*Sel, AMDGPU::OpName::src0);