Added SYS_MC_EST_GROUP to allow fine grained algorithm selection.

src/modules/systemlib/system_params.c

@@ -82,6 +82,22 @@ PARAM_DEFINE_INT32(SYS_USE_IO, 1);
  */
 PARAM_DEFINE_INT32(SYS_RESTART_TYPE, 2);
 
+/**
+ * Set multicopter estimator group
+ *
+ * Set the group of estimators used for multicopters and vtols
+ *
+ * @value 0 position_estimator_inav, attitude_estimator_q
+ * @value 1 local_position_estimator, attitude_estimator_q
+ * @value 2 ekf2
+ *
+ * @min 0
+ * @max 2
+ * @reboot_required true
+ * @group System
+ */
+PARAM_DEFINE_INT32(SYS_MC_EST_GROUP, 0);
+
 /**
  * Companion computer interface
  *