[libvirt] USB: USB Passthrough Device Autoconnect Feature

[Gonglei (Arei)]

Hi, all

Qemu upstream had achieved USB Passthrough Device Autoconnect Feature for the guest. 
Such as a USB device is unplugged from the host then plugged back in to the same USB physical port. 

the patch was:
https://lists.gnu.org/archive/html/qemu-devel/2011-05/msg02341.html

However, Libvirt has not provide such an interface that identifies a USB device for pass through with physical port, 
rather than the device number.

Do you have any ideas or plans about this problem? Thanks in advance.

Best Regards,
-Gonglei