Plane: ignore guided cmds from mavlink if we're in avoidADSB.

This change makes it behave like MAVLINK_MSG_ID_SET_POSITION_TARGET_LOCAL_NED

ArduPlane/GCS_Mavlink.cpp

@@ -1168,8 +1168,7 @@ void GCS_MAVLINK_Plane::handleMessage(const mavlink_message_t &msg)
         // in e.g., RTL, CICLE. Specifying a single mode for companion
         // computer control is more safe (even more so when using
         // FENCE_ACTION = 4 for geofence failures).
-        if ((plane.control_mode != &plane.mode_guided) &&
-            (plane.control_mode != &plane.mode_avoidADSB)) { // don't screw up failsafes
+        if (plane.control_mode != &plane.mode_guided) { // don't screw up failsafes
             break; 
         }
 
@@ -1279,7 +1278,7 @@ void GCS_MAVLINK_Plane::handleMessage(const mavlink_message_t &msg)
         // in modes such as RTL, CIRCLE, etc.  Specifying ONLY one mode
         // for companion computer control is more safe (provided
         // one uses the FENCE_ACTION = 4 (RTL) for geofence failures).
-        if (plane.control_mode != &plane.mode_guided && plane.control_mode != &plane.mode_avoidADSB) {
+        if (plane.control_mode != &plane.mode_guided) {
             //don't screw up failsafes
             break;
         }