IVGCVSW-1865 - Support NHWC for Convolution2D (CpuRef)

	* Updated the ConvImpl.hpp to use DataLayoutIndex
	* Enabled unit test for CpuRef
	* Update CreateWorkload Tests for ref with NHWC

Change-Id: Id309b7ef677489d63dcb5e09bd48ab9624b5ebfb
diff --git a/src/backends/reference/test/RefLayerTests.cpp b/src/backends/reference/test/RefLayerTests.cpp
index 2137161..259739b 100644
--- a/src/backends/reference/test/RefLayerTests.cpp
+++ b/src/backends/reference/test/RefLayerTests.cpp
@@ -36,6 +36,8 @@
     Convolution2dAsymmetricPaddingLargerThanHalfKernelSizeTest)
 ARMNN_AUTO_TEST_CASE(SimpleConvolution2dAsymmetricPadding, Convolution2dAsymmetricPaddingTest)
 
+ARMNN_AUTO_TEST_CASE(SimpleConvolution2dSquareNhwc, SimpleConvolution2d3x3NhwcTest, false)
+
 // Depthwise Convolution
 ARMNN_AUTO_TEST_CASE(DepthwiseConvolution2d, DepthwiseConvolution2dTest, true)
 ARMNN_AUTO_TEST_CASE(DepthwiseConvolution2dUint8, DepthwiseConvolution2dUint8Test, true)