purge vehicle_vision_position alias

msg/vehicle_local_position.msg

src/modules/ekf2/ekf2_main.cpp

src/modules/mavlink/mavlink_messages.cpp

.../position_estimator_inav/position_estimator_inav_main.cpp

src/modules/sdlog2/sdlog2.c

src/modules/simulator/simulator.h

src/modules/simulator/simulator_mavlink.cpp