[turbofan] Drop obsolete unused JSStrictNotEqual operator.

src/compiler/js-generic-lowering.cc

Index: src/compiler/js-generic-lowering.cc
diff --git a/src/compiler/js-generic-lowering.cc b/src/compiler/js-generic-lowering.cc
index 79a3377462883504f9df2589df1b61ea031f48a8..6acb50cc4c45380d061b0bce7a96983efc9641d9 100644
--- a/src/compiler/js-generic-lowering.cc
+++ b/src/compiler/js-generic-lowering.cc
@@ -127,15 +127,6 @@ void JSGenericLowering::LowerJSStrictEqual(Node* node) {
                       Operator::kEliminatable);
 }
 
-void JSGenericLowering::LowerJSStrictNotEqual(Node* node) {
-  // The !== operator doesn't need the current context.
-  NodeProperties::ReplaceContextInput(node, jsgraph()->NoContextConstant());
-  Callable callable = CodeFactory::StrictNotEqual(isolate());
-  node->RemoveInput(4);  // control
-  ReplaceWithStubCall(node, callable, CallDescriptor::kNoFlags,
-                      Operator::kEliminatable);
-}
-
 void JSGenericLowering::LowerJSToBoolean(Node* node) {
   // The ToBoolean conversion doesn't need the current context.
   NodeProperties::ReplaceContextInput(node, jsgraph()->NoContextConstant());