Allow users to customize the network_interface option is the network
config. For bridge this allows users to change the bridge name and for
maclvan it will be the same as `--opt parent=...`.
However the main reason for this option is to allow netavark plugins to
make use of it. I demoed the host-device plugin which makes use of this
as an example. While we could let users set them via --opt it is more
natural to just use the field which is designed for that purpose.
Signed-off-by: Paul Holzinger <pholzing@redhat.com>
ed99a979ce