s390: fixed doubleregister name

    fixed doubleregister name in VisitFloat64Ieee754Binop and VisitFloat64Ieee754Unop

R=joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2111873002
Cr-Commit-Position: refs/heads/master@{#37442}

src/compiler/s390/instruction-selector-s390.cc

@@ -1209,14 +1209,14 @@ void InstructionSelector::VisitFloat32Sqrt(Node* node) {
 void InstructionSelector::VisitFloat64Ieee754Unop(Node* node,
                                                   InstructionCode opcode) {
   S390OperandGenerator g(this);
-  Emit(opcode, g.DefineAsFixed(node, d0), g.UseFixed(node->InputAt(0), d0))
+  Emit(opcode, g.DefineAsFixed(node, d1), g.UseFixed(node->InputAt(0), d1))
       ->MarkAsCall();
 }
 
 void InstructionSelector::VisitFloat64Ieee754Binop(Node* node,
                                                    InstructionCode opcode) {
   S390OperandGenerator g(this);
-  Emit(opcode, g.DefineAsFixed(node, d0), g.UseFixed(node->InputAt(0), d0),
+  Emit(opcode, g.DefineAsFixed(node, d1), g.UseFixed(node->InputAt(0), d1),
        g.UseFixed(node->InputAt(1), d2))
       ->MarkAsCall();
 }