drm/i915/dsi: Pass fixed_mode to *_dsi_add_properties()

We want to eventually get rid of the connector->panel.fixed_mode
pointer so avoid using it during DSI property setup. Since this
all happens during the encoder init we already have the fixed_mode
around, just pass that in.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220311172428.14685-2-ville.syrjala@linux.intel.com


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