Revert "drm/i915: no lvds quirk for Zotac ZDBOX SD ID12/ID13"

This reverts commit 9756fe38.

The bogus lvds output is actually a lvds->hdmi bridge, which we don't
really support. But unconditionally disabling it breaks some existing
setups.

Reported-by: John Tapsell <johnflux@gmail.com>
References: http://permalink.gmane.org/gmane.comp.freedesktop.xorg.drivers.intel/17237


Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>