COMPMID-556: Fixes bias in CLDirectConvolutionLayer to be int32.

Biases were incorrectly passed as uchar8 in asymmetric quantized
calculations while they should be in int32.

Change-Id: I461f5e4ef6eb44374c1094378a1bfe9ade5e247d
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/96244
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
diff --git a/arm_compute/runtime/CL/functions/CLDirectConvolutionLayer.h b/arm_compute/runtime/CL/functions/CLDirectConvolutionLayer.h
index c2a55e4..45fd0c7 100644
--- a/arm_compute/runtime/CL/functions/CLDirectConvolutionLayer.h
+++ b/arm_compute/runtime/CL/functions/CLDirectConvolutionLayer.h
@@ -47,7 +47,8 @@
      *                       while every optional dimension from 4 and above represent a batch of inputs.
      *                       Data types supported: QASYMM8/QS8/QS16/F16/F32.
      * @param[in]  weights   Weights tensor. Weights are 4D tensor with dimensions [kernel_x, kernel_y, IFM, OFM]. Data type supported:Same as @p input.
-     * @param[in]  biases    Biases tensor. Shared biases supported. Biases are 1D tensor with dimensions [OFM]. Data type supported:Same as @p input.
+     * @param[in]  biases    Biases tensor. Shared biases supported. Biases are 1D tensor with dimensions [OFM].
+     *                       Data type supported: Should match @p input data type, except for input of QASYMM8 type where biases should be of S32 type.
      * @param[out] output    Destination tensor. 3 lower dimensions represent a single output [width, height, OFM], while the rest represent batch of outputs.
      *                       Data types supported: Same as @p input.
      * @param[in]  conv_info Contains padding and stride information described in @ref PadStrideInfo.