[PowerPC] Remove unnecessary braces in PPCVSXFMAMutate

Address Eric's post-commit review of r245741. NFC.

llvm-svn: 246121

llvm/lib/Target/PowerPC/PPCVSXFMAMutate.cpp

@@ -103,10 +103,10 @@ protected:
 
         VNInfo *AddendValNo =
           LIS->getInterval(MI->getOperand(1).getReg()).Query(FMAIdx).valueIn();
-        if (!AddendValNo) {
-          // This can be null if the register is undef.
+
+        // This can be null if the register is undef.
+        if (!AddendValNo)
           continue;
-        }
 
         MachineInstr *AddendMI = LIS->getInstructionFromIndex(AddendValNo->def);