IVGCVSW-3076 Add ConcatLayer methods to public API

!armnn:1119

Change-Id: Ic187f49427e38345f279537ed10a9275980c1360
Signed-off-by: Jim Flynn <jim.flynn@arm.com>
diff --git a/1.0/HalPolicy.cpp b/1.0/HalPolicy.cpp
index 158f0e3..fa29f86 100644
--- a/1.0/HalPolicy.cpp
+++ b/1.0/HalPolicy.cpp
@@ -292,7 +292,7 @@
     std::transform(inputHandles.begin(), inputHandles.end(), std::back_inserter(inputTensorInfos),
         [](const LayerInputHandle& h) -> const armnn::TensorInfo*{ return &h.GetTensorInfo(); });
     if (!IsLayerSupportedForAnyBackend(__func__,
-                                       armnn::IsMergerSupported,
+                                       armnn::IsConcatSupported,
                                        data.m_Backends,
                                        inputTensorInfos,
                                        outputInfo,
@@ -301,7 +301,7 @@
         return false;
     }
 
-    armnn::IConnectableLayer* layer = data.m_Network->AddMergerLayer(mergerDescriptor);
+    armnn::IConnectableLayer* layer = data.m_Network->AddConcatLayer(mergerDescriptor);
     assert(layer != nullptr);
     layer->GetOutputSlot(0).SetTensorInfo(outputInfo);