network: save network status when firewall rules are reloaded

network: save network status when firewall rules are reloaded

In the case that a new version of libvirt is started that uses
different rules to build the network firewall, we need to re-save the
status so that when the network is destroyed (or the *next* time
libvirt is restarted and wants to remove/re-add the firewall), it will
have the proper information to perform the firewall removal.

Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>