factory-config: Remove duplicate "ietf-ip:ipv6" node

Signed-off-by: Mattias Walström <[email protected]>

Author: mattiaswal

board/aarch64/bananapi-bpi-r3/rootfs/usr/share/product/bananapi,bpi-r3/etc/factory-config.cfg

@@ -99,7 +99,6 @@
       {
         "name": "wan",
         "type": "infix-if-type:ethernet",
-        "ietf-ip:ipv6": {},
         "ietf-ip:ipv4": {
           "infix-dhcp-client:dhcp": {
             "option": [

board/aarch64/friendlyarm-nanopi-r2s/rootfs/usr/share/product/friendlyarm,nanopi-r2s/etc/factory-config.cfg

@@ -58,7 +58,6 @@
       {
         "name": "wan",
         "type": "infix-if-type:ethernet",
-        "ietf-ip:ipv6": {},
         "ietf-ip:ipv4": {
           "infix-dhcp-client:dhcp": {
             "option": [