snabb-softwire-v2: warn on duplicate b4-ipv6 when transl. to ietf
snabb-softwire-v2: warn on duplicate b4-ipv6 when transl. to ietf

eugeneia/snabb,Igalia/snabb,Igalia/snabbswitch,snabbco/snabb,SnabbCo/snabbswitch,eugeneia/snabb,SnabbCo/snabbswitch,Igalia/snabbswitch,eugeneia/snabb,eugeneia/snabb,eugeneia/snabb,eugeneia/snabb,snabbco/snabb,alexandergall/snabbswitch,Igalia/snabb,eugeneia/snabb,Igalia/snabbswitch,snabbco/snabb,Igalia/snabb,Igalia/snabb,Igalia/snabbswitch,snabbco/snabb,alexandergall/snabbswitch,SnabbCo/snabbswitch,alexandergall/snabbswitch,Igalia/snabb,Igalia/snabb,alexandergall/snabbswitch,Igalia/snabb,snabbco/snabb,alexandergall/snabbswitch,alexandergall/snabbswitch,Igalia/snabbswitch,snabbco/snabb,Igalia/snabb,snabbco/snabb,snabbco/snabb,SnabbCo/snabbswitch,alexandergall/snabbswitch,eugeneia/snabb,alexandergall/snabbswitch