Javadoc fixes

Change-Id: Id23ed2d576b2222194153be9d043ca5acafe67ae
diff --git a/utils/misc/src/main/java/org/onlab/packet/IGMPMembership.java b/utils/misc/src/main/java/org/onlab/packet/IGMPMembership.java
index 174bd6f..495e283 100644
--- a/utils/misc/src/main/java/org/onlab/packet/IGMPMembership.java
+++ b/utils/misc/src/main/java/org/onlab/packet/IGMPMembership.java
@@ -78,8 +78,8 @@
      *
      * @param bb the ByteBuffer wrapping the serialized message.  The position of the
      *           ByteBuffer should be pointing at the head of either message type.
-     * @return
-     * @throws DeserializationException
+     * @return IGMP Group
+     * @throws DeserializationException if deserialization fails
      */
     public IGMPGroup deserialize(ByteBuffer bb) throws DeserializationException {
 
@@ -155,4 +155,4 @@
         result = prime * result + this.sources.hashCode();
         return result;
     }
-}
\ No newline at end of file
+}