drm_hwcomposer: Apply same logic for 'CURSOR' layers as for 'DEVICE'

Cursor usually is most top layer. Since it validates as CLIENT, it causes
remain layers to be validated as CLIENT, resulting performance dropping.

Signed-off-by: Roman Stratiienko <roman.stratiienko@globallogic.com>
1 job for hw-cursor-pr in 1 minute and 28 seconds (queued for 1 second)