[turbofan] Introduce TruncateTaggedToWord32 simplified operator.

src/compiler/machine-operator-reducer.h

Index: src/compiler/machine-operator-reducer.h
diff --git a/src/compiler/machine-operator-reducer.h b/src/compiler/machine-operator-reducer.h
index 7f8ff1a5fd6bd33a70a653acefdfbdf31e823695..cddf13d9d4c859e4eb14ecf17f5eb8987daf4c76 100644
--- a/src/compiler/machine-operator-reducer.h
+++ b/src/compiler/machine-operator-reducer.h
@@ -70,7 +70,6 @@ class MachineOperatorReducer final : public Reducer {
   Reduction ReduceUint32Div(Node* node);
   Reduction ReduceInt32Mod(Node* node);
   Reduction ReduceUint32Mod(Node* node);
-  Reduction ReduceTruncateFloat64ToInt32(Node* node);
   Reduction ReduceStore(Node* node);
   Reduction ReduceProjection(size_t index, Node* node);
   Reduction ReduceWord32Shifts(Node* node);