Fix javadoc generation not working with JDK 11

By updating the maven-javadoc-plugin in onos-dependencies.

Change-Id: Ibcbb9c0207ef52a1f398acd4afba38e11cad281e
diff --git a/app/src/main/java/org/opencord/dhcpl2relay/impl/DhcpL2Relay.java b/app/src/main/java/org/opencord/dhcpl2relay/impl/DhcpL2Relay.java
index 82de81b..e9c33b4 100755
--- a/app/src/main/java/org/opencord/dhcpl2relay/impl/DhcpL2Relay.java
+++ b/app/src/main/java/org/opencord/dhcpl2relay/impl/DhcpL2Relay.java
@@ -156,10 +156,10 @@
     @Reference(cardinality = ReferenceCardinality.MANDATORY)
     protected FlowObjectiveService flowObjectiveService;
 
-    /** Add option 82 to relayed packets */
+    /** Add option 82 to relayed packets. */
     protected boolean option82 = OPTION_82_DEFAULT;
 
-    /** Ask the DHCP Server to send back replies as L2 broadcast */
+    /** Ask the DHCP Server to send back replies as L2 broadcast. */
     protected boolean enableDhcpBroadcastReplies = ENABLE_DHCP_BROADCAST_REPLIES_DEFAULT;
 
     private DhcpRelayPacketProcessor dhcpRelayPacketProcessor =