drm/i915: Make force_load_detect effective even w/ DMI quirks/hotplug

drm/i915: Make force_load_detect effective even w/ DMI quirks/hotplug

When doing forced load detection testing we should totally ignore any
hotplug status for the connector. This is mostly relevant for machines
where we already ignore the hotplug status based on the DMI quirks. On
other machines we would currently skip the force load detection tests
on account of the connector already being connected.

v2: Drop the other force_load_detect check since it's useless now (Maarten)

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180322174135.5982-1-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>