Fix mwan3 package to support ipv6
With failover to lte activated mwan3 will cut ipv6 on PPPOE https://forum.turris.cz/t/ipv6-and-failover-to-lte/4524/2
With failover to lte activated mwan3 will cut ipv6 on PPPOE https://forum.turris.cz/t/ipv6-and-failover-to-lte/4524/2