IVGCVSW-3993 Add frontend and reference workload for ComparisonLayer

* Added frontend for ComparisonLayer
* Added RefComparisonWorkload
* Deprecated and removed Equal and Greater layers and workloads
* Updated tests to ensure backward compatibility

Signed-off-by: Aron Virginas-Tar <Aron.Virginas-Tar@arm.com>
Change-Id: Id50c880be1b567c531efff919c0c366d0a71cbe9
diff --git a/src/armnn/Network.cpp b/src/armnn/Network.cpp
index b2fc1a6..857f6b3 100644
--- a/src/armnn/Network.cpp
+++ b/src/armnn/Network.cpp
@@ -938,6 +938,12 @@
     return m_Graph->AddLayer<BatchToSpaceNdLayer>(batchToSpaceNdDescriptor, name);
 }
 
+IConnectableLayer* Network::AddComparisonLayer(const ComparisonDescriptor& comparisonDescriptor,
+                                               const char* name)
+{
+    return m_Graph->AddLayer<ComparisonLayer>(comparisonDescriptor, name);
+}
+
 IConnectableLayer* Network::AddFullyConnectedLayerImpl(const FullyConnectedDescriptor& fullyConnectedDescriptor,
                                                        const ConstTensor& weights,
                                                        const Optional<ConstTensor>& biases,
@@ -1436,12 +1442,12 @@
 
 IConnectableLayer* Network::AddGreaterLayer(const char* name)
 {
-    return m_Graph->AddLayer<GreaterLayer>(name);
+    return AddComparisonLayer(ComparisonDescriptor(ComparisonOperation::Greater), name);
 }
 
 IConnectableLayer* Network::AddEqualLayer(const char* name)
 {
-    return m_Graph->AddLayer<EqualLayer>(name);
+    return AddComparisonLayer(ComparisonDescriptor(ComparisonOperation::Equal), name);
 }
 
 IConnectableLayer* Network::AddRsqrtLayer(const char * name)