RBF: The operation of renaming a multi-subcluster directory to a single-cluster directory should throw ioexception

The operation of renaming a multi-subcluster directory to a single-cluster directory may cause inconsistent behavior of the file system. This operation should throw exception to be reasonable.

Examples are as follows:
1. add  hash_all mount point   `hdfs dfsrouteradmin -add /tmp/foo subcluster1,subcluster2  /tmp/foo -order HASH_ALL`
2. add   mount point   `hdfs dfsrouteradmin -add /user/foo subcluster1 /user/foo`
3. mkdir dir for all subcluster.  ` hdfs dfs -mkdir /tmp/foo/123 `

4. check dir and all subclusters will have dir `/tmp/foo/123`
`hdfs dfs -ls /tmp/foo/` : will show dir `/tmp/foo/123`;
`hdfs dfs -ls hdfs://subcluster1/tmp/foo/` : will show dir `hdfs://subcluster1/tmp/foo/123`;
`hdfs dfs -ls hdfs://subcluster2/tmp/foo/` : will show dir `hdfs://subcluster2/tmp/foo/123`;

5. rename `/tmp/foo/123` to `/user/foo/123`. The op will succeed. `hdfs dfs -mv /tmp/foo/123 /user/foo/123 `

6. check dir again, rbf cluster still show dir `/tmp/foo/123`
`hdfs dfs -ls /tmp/foo/` : will show dir `/tmp/foo/123`;
`hdfs dfs -ls hdfs://subcluster1/tmp/foo/` : will no dirs;
`hdfs dfs -ls hdfs://subcluster2/tmp/foo/` : will show dir `hdfs://subcluster2/tmp/foo/123`;

The step 5 should throw exception.