COMPIMID-523: Fix CLDepthwiseConvolution test.

The specified output size of the failing test case was invalid.
Additionally the kernel has been cleaned up and asserts have been added
in case of invalid configurations.

Change-Id: I198f3574f003b71968e4081a54cf102d748af5c1
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/88821
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Steven Niu <steven.niu@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
6 files changed