Fix: resolve CLI auto-completion issue of openstack apps

Change-Id: I0dc973628910cae3588f25e066e81a87a4264f06
diff --git a/apps/openstackvtap/app/src/main/java/org/onosproject/openstackvtap/cli/OpenstackVtapListCommand.java b/apps/openstackvtap/app/src/main/java/org/onosproject/openstackvtap/cli/OpenstackVtapListCommand.java
index 089f850..8826952 100644
--- a/apps/openstackvtap/app/src/main/java/org/onosproject/openstackvtap/cli/OpenstackVtapListCommand.java
+++ b/apps/openstackvtap/app/src/main/java/org/onosproject/openstackvtap/cli/OpenstackVtapListCommand.java
@@ -18,6 +18,7 @@
 import com.google.common.collect.ImmutableSet;
 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.DeviceId;
@@ -46,6 +47,7 @@
     @Argument(index = 0, name = "type",
             description = "vtap type [any|all|rx|tx]",
             required = false, multiValued = false)
+    @Completion(VtapTypeCompleter.class)
     String vtapType = "any";
 
     private static final String FORMAT = "ID { %s }: type [%s], srcIP [%s], dstIP [%s]";