Plane: use battery.has_current

ArduPlane/GCS_Mavlink.pde

@@ -254,7 +254,7 @@ static NOINLINE void send_extended_status1(mavlink_channel_t chan)
     int16_t battery_current = -1;
     int8_t battery_remaining = -1;
 
-    if (battery.monitoring() == AP_BATT_MONITOR_VOLTAGE_AND_CURRENT) {
+    if (battery.has_current()) {
         battery_remaining = battery.capacity_remaining_pct();
         battery_current = battery.current_amps() * 100;
     }