IVGCVSW-4246 Clean build of backends with -Wextra

Change-Id: I9e8d5576b3ec04c871785d5f2f9545bf1136e59b
Signed-off-by: Derek Lamberti <derek.lamberti@arm.com>
diff --git a/src/backends/backendsCommon/test/MockBackend.hpp b/src/backends/backendsCommon/test/MockBackend.hpp
index 437f23d..771e499 100644
--- a/src/backends/backendsCommon/test/MockBackend.hpp
+++ b/src/backends/backendsCommon/test/MockBackend.hpp
@@ -37,32 +37,32 @@
 
 class MockLayerSupport : public LayerSupportBase {
 public:
-    bool IsInputSupported(const TensorInfo& input,
-                          Optional<std::string&> reasonIfUnsupported = EmptyOptional()) const override
+    bool IsInputSupported(const TensorInfo& /*input*/,
+                          Optional<std::string&> /*reasonIfUnsupported = EmptyOptional()*/) const override
     {
         return true;
     }
 
-    bool IsOutputSupported(const TensorInfo& input,
-                          Optional<std::string&> reasonIfUnsupported = EmptyOptional()) const override
+    bool IsOutputSupported(const TensorInfo& /*input*/,
+                          Optional<std::string&> /*reasonIfUnsupported = EmptyOptional()*/) const override
     {
         return true;
     }
 
-    bool IsAdditionSupported(const TensorInfo& input0,
-                             const TensorInfo& input1,
-                             const TensorInfo& output,
-                             Optional<std::string&> reasonIfUnsupported = EmptyOptional()) const override
+    bool IsAdditionSupported(const TensorInfo& /*input0*/,
+                             const TensorInfo& /*input1*/,
+                             const TensorInfo& /*output*/,
+                             Optional<std::string&> /*reasonIfUnsupported = EmptyOptional()*/) const override
     {
         return true;
     }
 
-    bool IsConvolution2dSupported(const TensorInfo& input,
-                                  const TensorInfo& output,
-                                  const Convolution2dDescriptor& descriptor,
-                                  const TensorInfo& weights,
-                                  const Optional<TensorInfo>& biases,
-                                  Optional<std::string&> reasonIfUnsupported = EmptyOptional()) const override
+    bool IsConvolution2dSupported(const TensorInfo& /*input*/,
+                                  const TensorInfo& /*output*/,
+                                  const Convolution2dDescriptor& /*descriptor*/,
+                                  const TensorInfo& /*weights*/,
+                                  const Optional<TensorInfo>& /*biases*/,
+                                  Optional<std::string&> /*reasonIfUnsupported = EmptyOptional()*/) const override
     {
         return true;
     }