We have problems where systems simply stop booting and hang. This is due
to a lack of entropy which means ssh keys and networking can't be brought
up. Adding in the virtio-rng passthrough support allows host entropy to
pass into the guess and avoids these hangs.
This is particularly problematic after the gnutls upgrade which starts
using /dev/random instead of /dev/urandom but was an issue we'd occasionally
seem before that.
It particualrly affected x86 and ppc machines for some reason.
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
