[Lguest] more network interfaces

[inflo]

hi,
i was thinking about more network interfaces inside an guest, i think
there two ways, one to setup the guest at startup with more network,
e.g. --tunnet=192.168.3.1;192.168.4.1  but then a guest must be
restarted if one want more interfaces. So the second one would be a
hypercall to setup a new field in devices.descpage and call the rest
stuff like add_lguest_device().

thats my thoughts, some advantages/disadvantages or better ideas are
welcome.

flo