COMPMID-1603: Add PadLayer to graph API

Change-Id: Ic985ac8b0b09c3a6b3f2d43274af8ce89f8c90dd
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/150313
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Tested-by: bsgcomp <bsgcomp@arm.com>
diff --git a/src/graph/backends/NEON/NENodeValidator.cpp b/src/graph/backends/NEON/NENodeValidator.cpp
index 0bc3339..4f35298 100644
--- a/src/graph/backends/NEON/NENodeValidator.cpp
+++ b/src/graph/backends/NEON/NENodeValidator.cpp
@@ -59,6 +59,8 @@
                    NEDepthwiseConvolutionLayer3x3>(*polymorphic_downcast<DepthwiseConvolutionLayerNode *>(node));
         case NodeType::NormalizePlanarYUVLayer:
             return ARM_COMPUTE_CREATE_ERROR(arm_compute::ErrorCode::RUNTIME_ERROR, "Unsupported operation : NormalizePlanarYUVLayer");
+        case NodeType::PadLayer:
+            return ARM_COMPUTE_CREATE_ERROR(arm_compute::ErrorCode::RUNTIME_ERROR, "Unsupported operation : PadLayer");
         case NodeType::PermuteLayer:
             return detail::validate_permute_layer<NEPermute>(*polymorphic_downcast<PermuteLayerNode *>(node));
         case NodeType::ReorgLayer: