drm/i915: Add no_lvds entry for the Clientron U800

BugLink: http://bugs.launchpad.net/ubuntu/bugs/544671



This system claims to have a LVDS but has not.

Signed-off-by: Stephane Graber <stgraber@ubuntu.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
CC: stable@kernel.org
Signed-off-by: Eric Anholt <eric@anholt.net>