IVGCVSW-2915 Add Merge Layer and no-op factory method

Change-Id: I54549671e0d3b207904cf9796a843eb2b0a631f7
Signed-off-by: Nattapat Chaimanowong <nattapat.chaimanowong@arm.com>
diff --git a/src/backends/backendsCommon/LayerSupportBase.cpp b/src/backends/backendsCommon/LayerSupportBase.cpp
index 04f822c..fc2d502 100644
--- a/src/backends/backendsCommon/LayerSupportBase.cpp
+++ b/src/backends/backendsCommon/LayerSupportBase.cpp
@@ -253,6 +253,14 @@
     return DefaultLayerSupport(__func__, __FILE__, __LINE__, reasonIfUnsupported);
 }
 
+bool LayerSupportBase::IsMergeSupported(const TensorInfo& input0,
+                                        const TensorInfo& input1,
+                                        const TensorInfo& output,
+                                        Optional<std::string&> reasonIfUnsupported) const
+{
+    return DefaultLayerSupport(__func__, __FILE__, __LINE__, reasonIfUnsupported);
+}
+
 bool LayerSupportBase::IsMergerSupported(const std::vector<const TensorInfo*> inputs,
                                          const TensorInfo& output,
                                          const OriginsDescriptor& descriptor,