Now we have the following behavior:
1) object_new() returns an object with ref = 1
2) object_initialize() does not increase the reference count (ref may be 0).
3) object_deref() will finalize the object when ref = 0. it does not free the
memory associated with the object.
4) both link and child properties correctly set the reference count.
The expected usage is the following:
1) child devices should generally be created via object_initialize() using
memory from the parent device. Adding the object as a child property will
take ownership of the object and tie the child's life cycle to the parent.
2) If a child device is created via qdev_create() or some other form of
object_new(), there must be an object_delete() call in the parent device's
finalize function.