Skip intel_crt_init for Dell XPS 8700

The Dell XPS 8700 has a onboard Display port and HDMI port and no VGA port.
The call intel_crt_init freeze the machine, so skip such call.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=73559


Signed-off-by: Giacomo Comes <comes at naic.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>