[FS#539] Add "Prefix Delegation:" under WAN IPv6 on the status page in LuCI

[LEDE Bugs]

The following task has a new comment added:

FS#539 - Add "Prefix Delegation:" under  WAN IPv6 on the status page in LuCI
User who did this - Hannu Nyman (hnyman)

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Presenting ipv6-pd info on the LuCI front page has actually been implemented in master after lede-1701 was branched. See LuCI PR981:
https://github.com/openwrt/luci/pull/981

I tested backporting that to 17.01 and it seems to works ok:


Type: dhcpv6-pd
Prefix Delegated: 2001:14ba:8888:6666::/56
Address: 2001:14ba:8888::2:eed3/128
Gateway: fe80::200:5eff:fe00:101
DNS 1: 2001:14b8:1000::1
DNS 2: 2001:14b8:1000::2
Connected: 0h 8m 10s


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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=539#comment1884