SimulatedDataSet should not create DatanodeRegistration with namenode layout version and type

In DataNode.createBPRegistration(..), it creates storageInfo with nsInfo for the case of SimulatedDataSet. Then, the layout version and the node type will be respectively set to namenode's layout version and NodeType.NAME_NODE.

//DataNode.createBPRegistration(..)
    if (storageInfo == null) {
      // it's null in the case of SimulatedDataSet
      storageInfo = new StorageInfo(nsInfo);
    }