Fix Javadoc warnings

Change-Id: Ia5fe7785f76da92abbf940599cbd3d7dc6ac2cc5
diff --git a/core/api/src/main/java/org/onosproject/net/group/GroupStore.java b/core/api/src/main/java/org/onosproject/net/group/GroupStore.java
index 2cf4aa5..776cc60 100644
--- a/core/api/src/main/java/org/onosproject/net/group/GroupStore.java
+++ b/core/api/src/main/java/org/onosproject/net/group/GroupStore.java
@@ -187,6 +187,8 @@
 
     /**
      * Indicates failover within a failover group.
+     *
+     * @param failoverGroups groups to notify
      */
     void notifyOfFailovers(Collection<Group> failoverGroups);
 }