Add get_hotplug_handler() method to machine, and
make bus-less device use it during hotplug
as a means to discover a hotplug handler controller.
The returned controller is used to perform hotplug
actions.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>