add IPv6 record for iodine (OTRS)

add AAAA record for iodine, which already has a mapped
IPv6 address configured via puppet

this is the OTRS box (ticket.wm.org)

RT: 8442
Bug: 71262
Change-Id: I62b341c758df0aa63482ac09620051d92c1083e0
Merge "add IPv6 record for iodine (OTRS)"