If drmModeGetConnector() fails in drmmode_output_detect(), we have to
reset the output_id to -1 too.
Yet another spot leading to a potential NULL dereference when handling
the mode_output member as output_id was != -1. Though, this case should
be very hard to hit.
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Daniel Martin <consume.noise@gmail.com>
6804875662