Leave behind some debugging clues in case some panels don't work
properly.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/b36302b24676af511f4bbf702be21cc7e8f987c2.1474286487.git.jani.nikula@intel.com