EKF: Clean up wind state activation logic

Ensure wind states are deactivated in one place and always when in a non-position mode.
Activate wind states separately for each observation method.

EKF/airspeed_fusion.cpp

@@ -158,6 +158,7 @@ void Ekf::fuseAirspeed()
 
 	if (is_fused) {
 		_time_last_arsp_fuse = _time_last_imu;
+		_control_status.flags.fuse_aspd = true;
 	}
 }