COMPMID-2762: Add support for QASYMM8_SIGNED in CLReductionOperation and CLReduceMean

Change-Id: Ib6babd9ad80c57cf21c2f0ee2aab404221088595
Signed-off-by: Michalis Spyrou <michalis.spyrou@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/2670
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
diff --git a/arm_compute/runtime/CL/functions/CLReduceMean.h b/arm_compute/runtime/CL/functions/CLReduceMean.h
index 20105a5..30000ed 100644
--- a/arm_compute/runtime/CL/functions/CLReduceMean.h
+++ b/arm_compute/runtime/CL/functions/CLReduceMean.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2019 ARM Limited.
+ * Copyright (c) 2018-2020 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -45,7 +45,7 @@
      *
      * @note Supported tensor rank: up to 4
      *
-     * @param[in]  input          Source tensor. Data type supported: QASYMM8/F16/F32
+     * @param[in]  input          Source tensor. Data type supported: QASYMM8/QASYMM8_SIGNED/F16/F32
      * @param[in]  reduction_axis Reduction axis vector.
      * @param[in]  keep_dims      If positive, retains reduced dimensions with length 1.
      * @param[out] output         Destination tensor. Data type supported: Same as @p input
@@ -54,7 +54,7 @@
 
     /** Static function to check if given info will lead to a valid configuration of @ref CLReduceMean
      *
-     * @param[in] input          Source tensor. Data type supported: QASYMM8/F16/F32
+     * @param[in] input          Source tensor. Data type supported: QASYMM8/QASYMM8_SIGNED/F16/F32
      * @param[in] reduction_axis Reduction axis vector.
      * @param[in] keep_dims      If positive, retains reduced dimensions with length 1.
      * @param[in] output         Destination tensor. Data type supported: Same as @p input