- rtsol should be work for only one interface
- new variable ipv6_defaultrouter is added
- option name of rtadvd in comment are corrected
- ipv6_firewall_enable, ipv6_firewall_type, ipv6_firewall_script,
ipv6_firewall_logging are added to introduce rc.firewall6.
IPv6 firewall rule is just starting point and should be brushed up.
This commit includes PR18621, PR21694, PR22051.
PR: conf/18621, conf/21694, conf/22051
Reviewed by: asmodai
