Plane: fix to gps present check in mavlink extended status 1 msg

ArduPlane/GCS_Mavlink.pde

@@ -138,7 +138,7 @@ static NOINLINE void send_extended_status1(mavlink_channel_t chan, uint16_t pack
         control_sensors_present |= (1<<2); // compass present
     }
     control_sensors_present |= (1<<3); // absolute pressure sensor present
-    if (g_gps != NULL && g_gps->status() >= GPS::NO_GPS) {
+    if (g_gps != NULL && g_gps->status() > GPS::NO_GPS) {
         control_sensors_present |= (1<<5); // GPS present
     }
     control_sensors_present |= (1<<10); // 3D angular rate control