Add config node hnbgw/iuh/bind, taking an IPv4 address.
Use this address to bind the Iuh server.
This is particularly useful for the ip.access nano3G, which is very sensitive
with SCTP addresses that don't respond to SCTP heartbeats. If the hnbgw listens
on 0.0.0.0, there will be SCTP heartbeats for all local interfaces on the
machine that the hnbgw runs on; the nano3G will interpret the "missing", or
rather, redundant heartbeat acks for the interfaces that aren't really related
to the Iuh server and assume a broken Iuh link, leading to an Iuh shutdown and
reconnection, looping every minute or so. By binding the hnbgw to only one
local interface, the SCTP addresses can be reduced and "missing" heartbeat acks
can be avoided.
Change-Id: Ie2749c152b878e17aa65dfb806826357d5c494f1
Neels Hofmeyr
f495b2347b