dyndns: Don't try to push anything if no ipv4/ipv6
dyndns: Don't try to push anything if no ipv4/ipv6

YunoHost/yunohost,YunoHost/moulinette-yunohost,YunoHost/yunohost,YunoHost/yunohost,YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/yunohost,YunoHost/moulinette-yunohost