mc_pos_control_param: MPC_YAW_MODE remove option "set by waypoint" because that

is executed at any time if triplet as valid yaw waypoint

src/modules/mc_pos_control/mc_pos_control_params.c

@@ -664,11 +664,11 @@ PARAM_DEFINE_INT32(MPC_OBS_AVOID, 0);
  * Specifies the heading in Auto.
  *
  * @min 0
- * @max 3
- * @value 0 set by waypoint
- * @value 1 towards waypoint
- * @value 2 towards home
- * @value 3 away from home
+ * @max 2
+ * @value 0 towards waypoint
+ * @value 1 towards home
+ * @value 2 away from home
+ * @value 3 along trajectory
  * @group Mission
  */
-PARAM_DEFINE_INT32(MPC_YAW_MODE, 1);
+PARAM_DEFINE_INT32(MPC_YAW_MODE, 0);