general fixes on VIO data access

ROMFS/px4fmu_common/init.d-posix/1013_iris_vision

msg/vehicle_odometry.msg

posix-configs/SITL/init/lpe/iris_vision

...odules/attitude_estimator_q/attitude_estimator_q_main.cpp

src/modules/ekf2/ekf2_main.cpp

.../local_position_estimator/BlockLocalPositionEstimator.cpp

.../local_position_estimator/BlockLocalPositionEstimator.hpp

src/modules/local_position_estimator/sensors/mocap.cpp

src/modules/local_position_estimator/sensors/vision.cpp

src/modules/mavlink/mavlink_messages.cpp

src/modules/simulator/simulator.h

src/modules/simulator/simulator_mavlink.cpp