Regroup vtbl definitions to one translation unit (#1167)

Move function declarations to a new header file, with relevant existing
documentation.

Signed-off-by: Marco Antognini <marco.antognini@arm.com>

test_conformance/math_brute_force/macro_binary.cpp

@@ -13,18 +13,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
+
 #include "function_list.h"
+#include "test_functions.h"
 #include "utility.h"
 
 #include <string.h>
 
-int TestMacro_Int_Float_Float(const Func *f, MTdata, bool relaxedMode);
-int TestMacro_Int_Double_Double(const Func *f, MTdata, bool relaxedMode);
-
-extern const vtbl _macro_binary = { "macro_binary", TestMacro_Int_Float_Float,
-                                    TestMacro_Int_Double_Double };
-
-
 static int BuildKernel(const char *name, int vectorSize, cl_uint kernel_count,
                        cl_kernel *k, cl_program *p, bool relaxedMode)
 {