Lower log level to debug for flow store backup location change message

Change-Id: Ib1d9322ead8febcb76950d5018fb526dc51fe5a8
diff --git a/core/store/dist/src/main/java/org/onosproject/store/flow/impl/NewDistributedFlowRuleStore.java b/core/store/dist/src/main/java/org/onosproject/store/flow/impl/NewDistributedFlowRuleStore.java
index fd5ddea..444441b 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/flow/impl/NewDistributedFlowRuleStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/flow/impl/NewDistributedFlowRuleStore.java
@@ -632,7 +632,7 @@
                     // TODO: Pick any available node as backup and ensure hand-off occurs when
                     // a new master is elected.
                 }
-                log.info("Backup location for {} has changed from {} to {}.",
+                log.debug("Backup location for {} has changed from {} to {}.",
                         deviceId, currentBackupNode, newBackupNode);
                 backupSenderExecutor.schedule(() -> backupFlowEntries(newBackupNode, Sets.newHashSet(deviceId)),
                         0,