gtphub VTY test: use only 127.0.0.1.
Add a second example config file for gtphub so that the VTY test can use
nonstandard ports.
diff --git a/openbsc/doc/examples/osmo-gtphub/osmo-gtphub-1iface.cfg b/openbsc/doc/examples/osmo-gtphub/osmo-gtphub-1iface.cfg
new file mode 100644
index 0000000..3913d2c
--- /dev/null
+++ b/openbsc/doc/examples/osmo-gtphub/osmo-gtphub-1iface.cfg
@@ -0,0 +1,25 @@
+!
+! Osmocom gtphub configuration
+!
+! This file is used for VTY tests, referenced by openbsc/osmoappdesc.py
+! For the test, try to use most config commands.
+!
+
+line vty
+ no login
+
+gtphub
+ ! Local addresses to listen on and send from, both on one interface.
+ ! The side towards SGSN uses nonstandard ports.
+ bind-to-sgsns ctrl 127.0.0.1 12123 user 127.0.0.1 12153
+ ! The GGSN side with standard ports.
+ bind-to-ggsns 127.0.0.1
+
+ ! Proxy: unconditionally direct all traffic to...
+ sgsn-proxy 127.0.0.4
+
+ ! Proxy with nonstandard ports or separate IPs:
+ ggsn-proxy ctrl 127.0.0.3 2123 user 127.0.0.5 2152
+
+ ! Add a name server for GGSN resolution
+ grx-dns-add 192.168.0.1