[ONOS-7054] Implement prototype of ISSU protocol

Change-Id: Id543c0de9c97b68f977c824cbc987b35d81beb2d
diff --git a/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java b/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java
index 2de7dcc..d5deae1 100644
--- a/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java
+++ b/core/store/serializers/src/main/java/org/onosproject/store/serializers/KryoNamespaces.java
@@ -250,6 +250,7 @@
 import org.onosproject.store.service.Versioned;
 import org.onosproject.store.service.WorkQueueStats;
 import org.onosproject.ui.model.topo.UiTopoLayoutId;
+import org.onosproject.upgrade.Upgrade;
 
 import java.net.URI;
 import java.time.Duration;
@@ -627,6 +628,8 @@
                     PiCriterion.class,
                     PiInstruction.class
             )
+            .register(Upgrade.class)
+            .register(Upgrade.Status.class)
             .build("API");
 
     /**