drm/i915: Parse DP/eDP max lane count from VBT

Limit the DP lane count based on the new VBT DP/eDP max
lane count field.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220715202044.11153-13-ville.syrjala@linux.intel.com


Reviewed-by: Jani Nikula <jani.nikula@intel.com>