drm/i915/backlight: Disable backlight when using luminance control

We just return when using luminance control instead we should be
calling the disable helper to get everything cleaned up properly
by default.

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>
Link: https://lore.kernel.org/r/20250904044804.948391-1-suraj.kandpal@intel.com

Author: surajk8

drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c

@@ -550,9 +550,6 @@ static void intel_dp_aux_vesa_disable_backlight(const struct drm_connector_state
 	struct intel_panel *panel = &connector->panel;
 	struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder);
 
-	if (panel->backlight.edp.vesa.luminance_control_support)
-		return;
-
 	drm_edp_backlight_disable(&intel_dp->aux, &panel->backlight.edp.vesa.info);
 
 	if (!panel->backlight.edp.vesa.info.aux_enable)