IVGCVSW-2353 Ignore control inputs in TensorFlow parser

 * Allow control inputs from TensorFlow graph but ignore them in ArmNN graph.
 * Add utility function to test ArmNN graph structure.
 * Add ArmNN graph structure tests in TensorFlow paresr to ensure that control inputs
   are ignored in ArmNN graph as well as their inputs that are not used anywhere else.

Change-Id: Ib0ea0d2df85e3fc79b748fa4c9d20e0649352bc1
diff --git a/src/armnnTfParser/TfParser.hpp b/src/armnnTfParser/TfParser.hpp
index 0d1e497..20c5233 100644
--- a/src/armnnTfParser/TfParser.hpp
+++ b/src/armnnTfParser/TfParser.hpp
@@ -10,6 +10,7 @@
 #include "armnn/Tensor.hpp"
 #include "armnn/INetwork.hpp"
 
+#include <list>
 #include <map>
 #include <memory>
 #include <unordered_map>
@@ -241,6 +242,8 @@
     /// Map of TensorFlow operation names to parsing member functions.
     static const std::map<std::string, OperationParsingFunction> ms_OperationNameToParsingFunctions;
 
+    static const std::list<std::string> m_ControlInputs;
+
     std::map<std::string, armnn::TensorShape> m_InputShapes;
     std::vector<std::string> m_RequestedOutputs;