Use diamond operator

Change-Id: I9bb7e90ce7f45e65b4081a5bf85570b97e44712e
diff --git a/core/store/dist/src/main/java/org/onosproject/store/mastership/impl/RoleValue.java b/core/store/dist/src/main/java/org/onosproject/store/mastership/impl/RoleValue.java
index 9d3b168..5a38a34 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/mastership/impl/RoleValue.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/mastership/impl/RoleValue.java
@@ -45,9 +45,9 @@
      * Constructs empty RoleValue.
      */
     public RoleValue() {
-        value.put(MastershipRole.MASTER, new LinkedList<NodeId>());
-        value.put(MastershipRole.STANDBY, new LinkedList<NodeId>());
-        value.put(MastershipRole.NONE, new LinkedList<NodeId>());
+        value.put(MastershipRole.MASTER, new LinkedList<>());
+        value.put(MastershipRole.STANDBY, new LinkedList<>());
+        value.put(MastershipRole.NONE, new LinkedList<>());
     }
 
     /**