Add missing config option

configs/surface-6.13.config

@@ -22,6 +22,8 @@ CONFIG_CHARGER_SURFACE=m
 CONFIG_SENSORS_SURFACE_TEMP=m
 CONFIG_SENSORS_SURFACE_FAN=m
 
+CONFIG_RTC_DRV_SURFACE=m
+
 ##
 ## Surface Hotplug
 ##