[turbofan] Add new Float32Abs and Float64Abs operators.

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

Index: src/compiler/ppc/instruction-selector-ppc.cc
diff --git a/src/compiler/ppc/instruction-selector-ppc.cc b/src/compiler/ppc/instruction-selector-ppc.cc
index 9d576bafb7278d32c5baa049adf978f4ee4fce45..28a1649f8fc567c54c1c4753405a08dd655e0542 100644
--- a/src/compiler/ppc/instruction-selector-ppc.cc
+++ b/src/compiler/ppc/instruction-selector-ppc.cc
@@ -983,6 +983,12 @@ void InstructionSelector::VisitFloat64Min(Node* node) {
 }
 
 
+void InstructionSelector::VisitFloat32Abs(Node* node) { UNREACHABLE(); }
+
+
+void InstructionSelector::VisitFloat64Abs(Node* node) { UNREACHABLE(); }
+
+
 void InstructionSelector::VisitFloat32Sqrt(Node* node) {
   VisitRR(this, kPPC_SqrtDouble, node);
 }