Function offer_simple_device_unit

pub async fn offer_simple_device_unit<T: SimpleVmbusDevice>(
    driver_source: &VmTaskDriverSource,
    state_units: &StateUnits,
    vmbus: &VmbusServerHandle,
    device: T,
) -> Result<SpawnedUnit<SimpleChannelUnit<T>>>

Offers a simple vmbus device, creates a unit for it, and adds it to state_units.