NFS: Fix a refcounting issue in O_DIRECT

In nfs_direct_write_reschedule(), the requests from nfs_scan_commit_list
have a refcount of 2, whereas the operations in
nfs_direct_write_completion_ops expect them to have a refcount of 1.

This patch adds a call to release the extra references.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

fs/nfs/direct.c

@@ -490,6 +490,7 @@ static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
 			dreq->error = -EIO;
 			spin_unlock(cinfo.lock);
 		}
+		nfs_release_request(req);
 	}
 	nfs_pageio_complete(&desc);