Merge changes Ib965ef40,Ibc1e8048,I97c6be43,I1503ab39,I89ad254e, ... into main

* changes:
  Update doc for VEHICLE_SPEED_DISPLAY_UNITS.
  Update doc for HVAC_FAN_DIRECTION.
  Update doc for ELECTRONIC_STABILITY_CONTROL_STATE.
  Update doc for EV_STOPPING_MODE.
  Update doc for EV_BRAKE_REGENERATION_LEVEL.
  Update doc for CURRENT_GEAR.