Improve robustness to bad and lost airspeed data (#11846)

msg/vehicle_status.msg

src/modules/commander/Commander.cpp

src/modules/commander/Commander.hpp

src/modules/commander/commander_params.c

src/modules/fw_att_control/FixedwingAttitudeControl.cpp

src/modules/fw_pos_control_l1/FixedwingPositionControl.cpp