Copter: remove FlightMode_Avoid_ADSB.h file

ArduCopter/FlightMode_AVOID_ADSB.h

@@ -1,24 +0,0 @@
-class FlightMode_Avoid_ADSB : protected FlightMode_Guided {
-
-public:
-
-    FlightMode_Avoid_ADSB(Copter &copter) :
-        Copter::FlightMode_Guided(copter)        { }
-
-    bool init(bool ignore_checks) override;
-    void run() override;
-
-    bool requires_GPS() const override { return true; }
-    bool has_manual_throttle() const override { return false; }
-    bool allows_arming(bool from_gcs) const override { return false; }
-    bool is_autopilot() const override { return true; }
-
-    bool set_velocity(const Vector3f& velocity_neu);
-
-protected:
-
-    const char *name() const override { return "AVOID_ADSB"; }
-
-private:
-
-};