when creating a network, podman should add the firewall plugin to the
config but not specify a backend. this will allow cni to determine
whether it should use an iptables|firewalld backend.
Downstream-patch: podman-1805212.patch
Signed-off-by: Brent Baude <bbaude@redhat.com>
Signed-off-by: Valentin Rothberg <vrothberg@redhat.com>