Fix BUCK build for CordVtn by adding missing Openstack4j dependency

Change-Id: Ia0d5e04fd9cd31853da431297d97c34dc611a26a
diff --git a/BUCK b/BUCK
index 2f0387c..d8a87fb 100644
--- a/BUCK
+++ b/BUCK
@@ -3,10 +3,12 @@
     '//lib:org.apache.karaf.shell.console',
     '//lib:javax.ws.rs-api',
     '//lib:jsch',
+    '//lib:openstack4j-core',
+    '//lib:openstack4j-http-connector',
+    '//lib:openstack4j-httpclient',
     '//utils/rest:onlab-rest',
     '//cli:onos-cli',
     '//core/store/serializers:onos-core-serializers',
-    '//apps/openstackinterface:onos-app-openstackinterface-api',
     '//apps/dhcp/api:onos-apps-dhcp-api',
     '//protocols/ovsdb/api:onos-ovsdb-api',
     '//protocols/ovsdb/rfc:onos-ovsdb-rfc',