Fix: resolve CLI auto-completion issue of openstack apps

Change-Id: I0dc973628910cae3588f25e066e81a87a4264f06
diff --git a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/cli/OpenstackDirectPortAddCommand.java b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/cli/OpenstackDirectPortAddCommand.java
index 85da732..974c2cc 100644
--- a/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/cli/OpenstackDirectPortAddCommand.java
+++ b/apps/openstacknetworking/app/src/main/java/org/onosproject/openstacknetworking/cli/OpenstackDirectPortAddCommand.java
@@ -17,6 +17,7 @@
 
 import org.apache.karaf.shell.api.action.Argument;
 import org.apache.karaf.shell.api.action.Command;
+import org.apache.karaf.shell.api.action.Completion;
 import org.apache.karaf.shell.api.action.lifecycle.Service;
 import org.onosproject.cli.AbstractShellCommand;
 import org.onosproject.net.device.DeviceService;
@@ -42,6 +43,7 @@
         description = "Manually adds OpenStack direct ports to the device")
 public class OpenstackDirectPortAddCommand extends AbstractShellCommand {
     @Argument(index = 0, name = "port ID", description = "port ID", required = true)
+    @Completion(DirectPortListCompleter.class)
     private String portId = null;
 
     @Override