In the vhost-user example, a chardev with id chr0 is referenced by the
vhost-user net backend, but the id is not specified in the chardev option.
Signed-off-by: NVincenzo Maffione <v.maffione@gmail.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>