gsup_server: send routing error back to the correct peer

If a peer attempts to add a route to an ipa-name that we already have in the
routing system, don't send the routing error to the peer that already has the
name, but to the peer that attempts to re-use it and would cause the collision.

This is fixing a situation where for example a locally attached MSC has name
'MSC-1', and a remote site is proxying GSUP here for a remote MSC that also has
the name 'MSC-1'. Send the routing error back to the proxy, not local 'MSC-1'.

Change-Id: Icafaedc11b5925149d338bdcb987ae985a7323d6
1 file changed