COMPMID-2798 Add support for QASYMM8_SIGNED in NEArithmeticSubtraction

Change-Id: Ib90e0ce46f8dc006827d9ee9d95cf14e8b7832ad
Signed-off-by: Michalis Spyrou <michalis.spyrou@arm.com>
Reviewed-on: https://review.mlplatform.org/c/2415
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/tests/validation/fixtures/ArithmeticOperationsFixture.h b/tests/validation/fixtures/ArithmeticOperationsFixture.h
index 76f241c..086b52b 100644
--- a/tests/validation/fixtures/ArithmeticOperationsFixture.h
+++ b/tests/validation/fixtures/ArithmeticOperationsFixture.h
@@ -182,6 +182,20 @@
     }
 };
 
+template <typename TensorType, typename AccessorType, typename FunctionType>
+class ArithmeticSubtractionQuantSignedValidationFixture : public ArithmeticOperationGenericFixture<TensorType, AccessorType, FunctionType, qasymm8_signed_t>
+{
+public:
+    template <typename...>
+    void setup(const TensorShape &shape, DataType data_type0, DataType data_type1, DataType output_data_type, ConvertPolicy convert_policy,
+               QuantizationInfo in1_qua_info, QuantizationInfo in2_qua_info, QuantizationInfo out_qua_info)
+    {
+        ArithmeticOperationGenericFixture<TensorType, AccessorType, FunctionType, qasymm8_signed_t>::setup(reference::ArithmeticOperation::SUB, shape, shape,
+                                                                                                           data_type0, data_type1, output_data_type, convert_policy,
+                                                                                                           in1_qua_info, in2_qua_info, out_qua_info);
+    }
+};
+
 template <typename TensorType, typename AccessorType, typename FunctionType, typename T>
 class ArithmeticSubtractionValidationFixture : public ArithmeticOperationGenericFixture<TensorType, AccessorType, FunctionType, T>
 {