make GOE extend from util::Op (#2153)

* make GOE extend from util::Op

* fix build breaks

python/pyngraph/ops/get_output_element.cpp

@@ -26,7 +26,7 @@ void regclass_pyngraph_op_GetOutputElement(py::module m)
 {
     py::class_<ngraph::op::GetOutputElement,
                std::shared_ptr<ngraph::op::GetOutputElement>,
-               ngraph::Node>
+               ngraph::op::Op>
         get_output_element(m, "GetOutputElement");
     get_output_element.doc() = "ngraph.impl.op.GetOutputElement wraps ngraph::op::GetOutputElement";
     get_output_element.def(py::init<const std::shared_ptr<ngraph::Node>&, size_t>());

src/ngraph/op/get_output_element.cpp

@@ -22,7 +22,7 @@ using namespace std;
 using namespace ngraph;
 
 op::GetOutputElement::GetOutputElement(const shared_ptr<Node>& arg, size_t n)
-    : Node("GetOutputElement", {arg})
+    : Op("GetOutputElement", {arg})
     , m_n{n}
 {
     constructor_validate_and_infer_types();

src/ngraph/op/get_output_element.hpp

@@ -16,7 +16,7 @@
 
 #pragma once
 
-#include "ngraph/node.hpp"
+#include "ngraph/op/op.hpp"
 
 namespace ngraph
 {
@@ -25,7 +25,7 @@ namespace ngraph
         NodeVector get_output_elements(const std::shared_ptr<Node>& mon);
 
         /// \brief Operation to get an output from a node.
-        class GetOutputElement : public Node
+        class GetOutputElement : public Op
         {
         public:
             /// \brief Constructs a get-tuple-element operation.