Bug fix: make sure that divisor is non-zero value

Change-Id: I7214ebf552ba60db149db2b4edbb90f59d3bdd16
diff --git a/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageProvider.java b/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageProvider.java
index 8c9e160..93aa70f 100644
--- a/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageProvider.java
+++ b/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageProvider.java
@@ -106,7 +106,7 @@
         controller.getSwitches().forEach(sw -> sw.addEventListener(outMsgListener));
 
         executor = Executors.newSingleThreadScheduledExecutor(
-                groupedThreads("onos/provider", "aggregator"));
+                             groupedThreads("onos/provider", "aggregator"));
 
         connectInitialDevices();
         log.info("Started");