IVGCVSW-4633 Add conversion of BF16 support to Neon

 * Add NeonConvertBf16ToFp32Workload
 * Add NeonConvertFp32ToBf16Workload
 * Add BFloat16 type support to NeonConstantWorkload and NeonTensorHandle
 * Add ConvertBf16ToFp32Weight when ConvertBf16ToFp32Layer is added
 * Unit tests

Signed-off-by: Narumol Prangnawarat <narumol.prangnawarat@arm.com>
Change-Id: Id5b44a203add5e0c98c1ca4e2162115741b56644
diff --git a/src/backends/neon/NeonLayerSupport.cpp b/src/backends/neon/NeonLayerSupport.cpp
index c01a178..44e84fb 100644
--- a/src/backends/neon/NeonLayerSupport.cpp
+++ b/src/backends/neon/NeonLayerSupport.cpp
@@ -259,6 +259,16 @@
                                       &TrueFunc<>);
 }
 
+bool NeonLayerSupport::IsConvertBf16ToFp32Supported(const TensorInfo& input,
+                                                    const TensorInfo& output,
+                                                    Optional<std::string&> reasonIfUnsupported) const
+{
+    armnn::IgnoreUnused(input);
+    armnn::IgnoreUnused(output);
+    armnn::IgnoreUnused(reasonIfUnsupported);
+    return true;
+}
+
 bool NeonLayerSupport::IsConvertFp16ToFp32Supported(const TensorInfo& input,
                                                     const TensorInfo& output,
                                                     Optional<std::string&> reasonIfUnsupported) const
@@ -269,6 +279,16 @@
     return true;
 }
 
+bool NeonLayerSupport::IsConvertFp32ToBf16Supported(const TensorInfo& input,
+                                                    const TensorInfo& output,
+                                                    Optional<std::string&> reasonIfUnsupported) const
+{
+    armnn::IgnoreUnused(input);
+    armnn::IgnoreUnused(output);
+    armnn::IgnoreUnused(reasonIfUnsupported);
+    return true;
+}
+
 bool NeonLayerSupport::IsConvertFp32ToFp16Supported(const TensorInfo& input,
                                                     const TensorInfo& output,
                                                     Optional<std::string&> reasonIfUnsupported) const