drm/i915/icl: Fill DSI ports info

This patch fills backlight, CABC and general port
info for Gen11 DSI.

Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/48c9f867d61a60dc7c2ce744ac2325655652c55f.1543500286.git.jani.nikula@intel.com