ggsn: Add osmo-ggsn.cfg

Taken from docker-playground/ttcn3-ggsn-test/osmo-ggsn.cfg

Change-Id: Ifbd50b6c1ebfd0371bd384c4ae0c4dc763478f49
diff --git a/ggsn_tests/osmo-ggsn.cfg b/ggsn_tests/osmo-ggsn.cfg
new file mode 100644
index 0000000..5fdcf15
--- /dev/null
+++ b/ggsn_tests/osmo-ggsn.cfg
@@ -0,0 +1,80 @@
+!
+! OpenGGSN (0.94.1-adac) configuration saved from vty
+!!
+!
+log gsmtap 127.0.0.1
+ logging level set-all debug
+ logging filter all 1
+!
+log stderr
+ logging filter all 1
+ logging color 1
+ logging print category 1
+ logging timestamp 1
+ logging print extended-timestamp 1
+ logging level ip info
+ logging level tun info
+ logging level ggsn info
+ logging level sgsn notice
+ logging level icmp6 debug
+ logging level lglobal notice
+ logging level llapd notice
+ logging level linp notice
+ logging level lmux notice
+ logging level lmi notice
+ logging level lmib notice
+ logging level lsms notice
+ logging level lctrl notice
+ logging level lgtp info
+ logging level lstats notice
+ logging level lgsup notice
+ logging level loap notice
+ logging level lss7 notice
+ logging level lsccp notice
+ logging level lsua notice
+ logging level lm3ua notice
+ logging level lmgcp notice
+ logging level lgtp debug
+!
+stats interval 5
+!
+line vty
+ no login
+ bind 0.0.0.0
+!
+ggsn ggsn0
+ gtp state-dir /tmp
+ gtp bind-ip 127.0.0.2
+ apn internet
+  gtpu-mode tun
+  tun-device tun4
+  type-support v4
+  ip prefix dynamic 176.16.16.0/20
+  ip dns 0 172.18.3.201
+  ip dns 1 8.8.8.8
+  ip ifconfig 176.16.16.0/20
+  no shutdown
+ apn inet6
+  gtpu-mode tun
+  tun-device tun6
+  type-support v6
+  ipv6 prefix dynamic 2001:780:44:2000:0:0:0:0/56
+  ipv6 dns 0 fd02:db8:3::201
+  ipv6 dns 1 2001:4860:4860::8844
+  ipv6 ifconfig 2001:780:44:2000:0:0:0:0/56
+  no shutdown
+ apn inet46
+  gtpu-mode tun
+  tun-device tun46
+  type-support v4v6
+  ip prefix dynamic 176.16.32.0/20
+  ip dns 0 172.18.3.201
+  ip dns 1 8.8.8.8
+  ip ifconfig 176.16.32.0/20
+  ipv6 prefix dynamic 2001:780:44:2100:0:0:0:0/56
+  ipv6 dns 0 fd02:db8:3::201
+  ipv6 dns 1 2001:4860:4860::8844
+  ipv6 ifconfig 2001:780:44:2100:0:0:0:0/56
+  no shutdown
+ default-apn internet
+ no shutdown ggsn