PPC: [turbofan] Introduce optional Float64Min and Float64Max machine 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 56d683479b882d9eff945dc7be803cd44c40714a..4cfae16e2768c120b2ad64ebe3eefa3a7b4cb2cf 100644
--- a/src/compiler/ppc/instruction-selector-ppc.cc
+++ b/src/compiler/ppc/instruction-selector-ppc.cc
@@ -963,6 +963,12 @@ void InstructionSelector::VisitFloat64Mod(Node* node) {
 }
 
 
+void InstructionSelector::VisitFloat64Max(Node* node) { UNREACHABLE(); }
+
+
+void InstructionSelector::VisitFloat64Min(Node* node) { UNREACHABLE(); }
+
+
 void InstructionSelector::VisitFloat64Sqrt(Node* node) {
   VisitRRFloat64(this, kPPC_SqrtFloat64, node);
 }