Improve EntryStoreCompleter logging

Do not use DeferredPersistCallback.toString(), just log the delegate's
identity.

JIRA: CONTROLLER-2137
Change-Id: I5a236a9e43da7f37a3b6ef3143c7711bee60f9fa
Signed-off-by: Robert Varga <[email protected]>

Author: rovarga

raft/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/spi/EntryStoreCompleter.java

@@ -45,9 +45,9 @@ public void invoke(@Nullable Exception failure, Long success) {
                 delegate.invoke(failure, success);
             } finally {
                 if (deferred.remove(this)) {
-                    LOG.debug("{}: completed deferred callback {}", memberId, this);
+                    LOG.debug("{}: completed deferred callback {}", memberId, delegate);
                 } else {
-                    LOG.warn("{}: remove failed to find deferred callback, perhaps we already ran {}", memberId, this);
+                    LOG.warn("{}: remove failed to find deferred callback for {}", memberId, delegate);
                 }
             }
         }