jenkins: fix build of osmo-sgsn: use osmo-ggsn

osmo-sgsn change-id I91a126952ae75ae9ba1f42aac4d26413384bba5d and commit
a3b73e917b653d13d027cff2c95a56bbc1264446 has broken compatibility with
openggsn.git, by requiring current osmo-ggsn version (1.0.0).

Fix build fallout: use osmo-ggsn instead of openggsn.git.

Change-Id: I5161983ef625465e21b95578ab5648ecc73d6069
diff --git a/contrib/jenkins-build-osmo-sgsn.sh b/contrib/jenkins-build-osmo-sgsn.sh
index 1979e8c..45fae5e 100755
--- a/contrib/jenkins-build-osmo-sgsn.sh
+++ b/contrib/jenkins-build-osmo-sgsn.sh
@@ -8,7 +8,7 @@
 build_repo libosmo-abis
 build_repo libosmo-netif --disable-doxygen
 build_repo libosmo-sccp
-build_repo openggsn
+build_repo osmo-ggsn
 build_repo osmo-sgsn --disable-iu
 
 create_bin_tgz osmo-sgsn