NFSv4: Deal with some more sparse warnings

Technically, we don't really need to convert these time stamps,
since they are actually cookies.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <Chuck.Lever@oracle.com>
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 1a4a3bd..1336263 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1816,7 +1816,7 @@
 	*p++ = cpu_to_be32(RPC_AUTH_UNIX);			/* auth_sys */
 
 	/* authsys_parms rfc1831 */
-	*p++ = (__be32)nn->boot_time.tv_nsec;		/* stamp */
+	*p++ = cpu_to_be32(nn->boot_time.tv_nsec);	/* stamp */
 	p = xdr_encode_opaque(p, machine_name, len);
 	*p++ = cpu_to_be32(0);				/* UID */
 	*p++ = cpu_to_be32(0);				/* GID */