NFSv4 release the sequence id in the return on close case

Otherwise we deadlock if state recovery is initiated while we
sleep.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/nfs4proc.c

@@ -2275,9 +2275,11 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data)
 	if (calldata->arg.fmode == 0) {
 		task->tk_msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLOSE];
 		if (calldata->roc &&
-		    pnfs_roc_drain(inode, &calldata->roc_barrier, task))
+		    pnfs_roc_drain(inode, &calldata->roc_barrier, task)) {
+			nfs_release_seqid(calldata->arg.seqid);
 			goto out_wait;
 		    }
+	}
 
 	nfs_fattr_init(calldata->res.fattr);
 	calldata->timestamp = jiffies;