Fix the tools/vnet makefiles so that vnets will compile
and includes updates to the vnet implementation.
Vnet ids are increased to 128 bits. The vnet module will
insmod whether xen-br0 exists or not.
Signed-off-by: Mike Wray <mike.wray@hp.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>