This does not break ttcn3-sgsn-test since it uses a custom config file
with the correct IPs.
Change-Id: I2a922139c50d06217e5e6105ea65bf673daa10a8
Related: OS#1700
Since October 2017 the default config name no longer has an underscore
but a dash in the filename. See osmo-sgsn.git Change-Id
If804da17a7481e79e000fe40ae0d9c4be9722e61