drm/i915/icl: Add Y2xx and Y4xx (xx:10/12/16) plane control definitions

drm/i915/icl: Add Y2xx and Y4xx (xx:10/12/16) plane control definitions

Added needed plane control flag definitions for Y2xx and Y4xx (10, 12 and
16 bits)

Signed-off-by: Swati Sharma <swati2.sharma@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1551700595-21481-6-git-send-email-swati2.sharma@intel.com
Acked-by: Jani Nikula <jani.nikula@intel.com>