COMPMID-2600: Implement a new and generic depthwise convolution for CL QASYMM8 NHWC

The NCHW case is supported at function level by permuting the
inputs/outputs to NHWC.

This patch also removes CLDirectConvolutionLayerOutputStageKernel which
is deprecated and some kernels which were only used in the generic case
of depthwise convolution.

Change-Id: I91e0f02d0a2f4a4a352e08c248e648944137fe68
Signed-off-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Reviewed-on: https://review.mlplatform.org/c/2056
Reviewed-by: Giorgio Arena <giorgio.arena@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
diff --git a/src/core/CL/kernels/CLGEMMLowpQuantizeDownInt32ToUint8ScaleByFloatKernel.cpp b/src/core/CL/kernels/CLGEMMLowpQuantizeDownInt32ToUint8ScaleByFloatKernel.cpp
index 2967a73..ae096f2 100644
--- a/src/core/CL/kernels/CLGEMMLowpQuantizeDownInt32ToUint8ScaleByFloatKernel.cpp
+++ b/src/core/CL/kernels/CLGEMMLowpQuantizeDownInt32ToUint8ScaleByFloatKernel.cpp
@@ -35,8 +35,6 @@
 
 #include "support/ToolchainSupport.h"
 
-using namespace arm_compute;
-
 namespace arm_compute
 {
 namespace
@@ -101,8 +99,6 @@
 } // namespace
 
 class Coordinates;
-} // namespace arm_compute
-
 CLGEMMLowpQuantizeDownInt32ToUint8ScaleByFloatKernel::CLGEMMLowpQuantizeDownInt32ToUint8ScaleByFloatKernel()
     : _input(nullptr), _bias(nullptr), _output(nullptr)
 {
@@ -177,3 +173,4 @@
     }
     while(collapsed.slide_window_slice_3D(slice));
 }
+} // namespace arm_compute