action: remove max speed settings

This API is confusing as it only works for PX4 quads but not PX4
fixedwing or anything ArduPilot based.

The reason is that this just sets a PX4 parameter that is not
standardized via MAVLink.

Therefore, I suggest to remove the API and instead recommend to use
the param plugin to set the specific params specifically.

src/mavsdk/plugins/action/action.cpp

@@ -225,26 +225,6 @@ Action::Result Action::set_takeoff_altitude(float altitude) const
     return _impl->set_takeoff_altitude(altitude);
 }
 
-void Action::get_maximum_speed_async(const GetMaximumSpeedCallback callback)
-{
-    _impl->get_maximum_speed_async(callback);
-}
-
-std::pair<Action::Result, float> Action::get_maximum_speed() const
-{
-    return _impl->get_maximum_speed();
-}
-
-void Action::set_maximum_speed_async(float speed, const ResultCallback callback)
-{
-    _impl->set_maximum_speed_async(speed, callback);
-}
-
-Action::Result Action::set_maximum_speed(float speed) const
-{
-    return _impl->set_maximum_speed(speed);
-}
-
 void Action::get_return_to_launch_altitude_async(const GetReturnToLaunchAltitudeCallback callback)
 {
     _impl->get_return_to_launch_altitude_async(callback);

src/mavsdk/plugins/action/action_impl.cpp

@@ -716,35 +716,6 @@ std::pair<Action::Result, float> ActionImpl::get_takeoff_altitude() const
     }
 }
 
-void ActionImpl::set_maximum_speed_async(
-    const float speed_m_s, const Action::ResultCallback& callback) const
-{
-    callback(set_maximum_speed(speed_m_s));
-}
-
-Action::Result ActionImpl::set_maximum_speed(float speed_m_s) const
-{
-    const MavlinkParameterClient::Result result =
-        _system_impl->set_param_float(MAX_SPEED_PARAM, speed_m_s);
-    return (result == MavlinkParameterClient::Result::Success) ? Action::Result::Success :
-                                                                 Action::Result::ParameterError;
-}
-
-void ActionImpl::get_maximum_speed_async(const Action::GetMaximumSpeedCallback& callback) const
-{
-    auto speed_result = get_maximum_speed();
-    callback(speed_result.first, speed_result.second);
-}
-
-std::pair<Action::Result, float> ActionImpl::get_maximum_speed() const
-{
-    auto result = _system_impl->get_param_float(MAX_SPEED_PARAM);
-    return std::make_pair<>(
-        (result.first == MavlinkParameterClient::Result::Success) ? Action::Result::Success :
-                                                                    Action::Result::ParameterError,
-        result.second);
-}
-
 void ActionImpl::set_return_to_launch_altitude_async(
     const float relative_altitude_m, const Action::ResultCallback& callback) const
 {

src/mavsdk/plugins/action/action_impl.h

@@ -84,13 +84,6 @@ class ActionImpl : public PluginImplBase {
     Action::Result set_takeoff_altitude(float relative_altitude_m);
     std::pair<Action::Result, float> get_takeoff_altitude() const;
 
-    void
-    set_maximum_speed_async(const float speed_m_s, const Action::ResultCallback& callback) const;
-    void get_maximum_speed_async(const Action::GetMaximumSpeedCallback& callback) const;
-
-    Action::Result set_maximum_speed(float speed_m_s) const;
-    std::pair<Action::Result, float> get_maximum_speed() const;
-
     void set_return_to_launch_altitude_async(
         const float relative_altitude_m, const Action::ResultCallback& callback) const;
     void get_return_to_launch_altitude_async(

src/mavsdk/plugins/action/include/plugins/action/action.h

@@ -542,43 +542,6 @@ class Action : public PluginBase {
      */
     Result set_takeoff_altitude(float altitude) const;
 
-    /**
-     * @brief Callback type for get_maximum_speed_async.
-     */
-    using GetMaximumSpeedCallback = std::function<void(Result, float)>;
-
-    /**
-     * @brief Get the vehicle maximum speed (in metres/second).
-     *
-     * This function is non-blocking. See 'get_maximum_speed' for the blocking counterpart.
-     */
-    void get_maximum_speed_async(const GetMaximumSpeedCallback callback);
-
-    /**
-     * @brief Get the vehicle maximum speed (in metres/second).
-     *
-     * This function is blocking. See 'get_maximum_speed_async' for the non-blocking counterpart.
-     *
-     * @return Result of request.
-     */
-    std::pair<Result, float> get_maximum_speed() const;
-
-    /**
-     * @brief Set vehicle maximum speed (in metres/second).
-     *
-     * This function is non-blocking. See 'set_maximum_speed' for the blocking counterpart.
-     */
-    void set_maximum_speed_async(float speed, const ResultCallback callback);
-
-    /**
-     * @brief Set vehicle maximum speed (in metres/second).
-     *
-     * This function is blocking. See 'set_maximum_speed_async' for the non-blocking counterpart.
-     *
-     * @return Result of request.
-     */
-    Result set_maximum_speed(float speed) const;
-
     /**
      * @brief Callback type for get_return_to_launch_altitude_async.
      */

src/mavsdk/plugins/action/mocks/action_mock.h

@@ -29,8 +29,6 @@ class MockAction {
     MOCK_CONST_METHOD0(transition_to_multicopter, Action::Result()){};
     MOCK_CONST_METHOD0(get_takeoff_altitude, std::pair<Action::Result, float>()){};
     MOCK_CONST_METHOD1(set_takeoff_altitude, Action::Result(float)){};
-    MOCK_CONST_METHOD0(get_maximum_speed, std::pair<Action::Result, float>()){};
-    MOCK_CONST_METHOD1(set_maximum_speed, Action::Result(float)){};
     MOCK_CONST_METHOD0(get_return_to_launch_altitude, std::pair<Action::Result, float>()){};
     MOCK_CONST_METHOD1(set_return_to_launch_altitude, Action::Result(float)){};
     MOCK_CONST_METHOD1(set_current_speed, Action::Result(float)){};