Modify FAN_DIRECTION to be a bit mask

We are changing VehicleHvacFanDirection to be a bit mask so that any
combination of fan directions can be made.  This means that
HVAC_FAN_DIRECTION_AVAILABLE must now be a int32_vector.

Bug: 72221544
Test: Unit tests pass
Change-Id: I602871c95aa2429ea334ec85a879610c68979184
1 file changed