mc_pos_control: respect estimator max speed and min height limits

src/modules/mc_pos_control/mc_pos_control_params.c

@@ -437,6 +437,20 @@ PARAM_DEFINE_FLOAT(MPC_ACC_HOR, 5.0f);
  */
 PARAM_DEFINE_FLOAT(MPC_DEC_HOR_SLOW, 5.0f);
 
+/**
+ * Horizontal acceleration in manual modes when optical flow ground speed limit is removed.
+ * If full stick is being applied and the EKF starts using GPS whilst using optical flow,
+ * the vehicle will accelerate at this rate until the normal position control speed is achieved.
+ *
+ * @unit m/s/s
+ * @min 0.2
+ * @max 2.0
+ * @increment 0.1
+ * @decimal 1
+ * @group Multicopter Position Control
+ */
+PARAM_DEFINE_FLOAT(MPC_ACC_HOR_FLOW, 0.5f);
+
 /**
  * Maximum vertical acceleration in velocity controlled modes upward
  *