drm/i915/dsi: Skip delays for v3 VBTs in vid-mode

For v3 VBTs in vid-mode the delays are part of the VBT sequences, so
we should not also delay ourselves otherwise we get double delays.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Bob Paauwe <bob.j.paauwe@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1488374106-4949-11-git-send-email-jani.nikula@intel.com