nfsd: fix a warning message

The WARN() macro takes a condition and a format string.  The condition
was accidentally left out here so it just prints the function name
instead of the message.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs4state.c

@@ -2240,7 +2240,8 @@ nfsd4_store_cache_entry(struct nfsd4_compoundres *resp)
 	base = resp->cstate.data_offset;
 	slot->sl_datalen = buf->len - base;
 	if (read_bytes_from_xdr_buf(buf, base, slot->sl_data, slot->sl_datalen))
-		WARN("%s: sessions DRC could not cache compound\n", __func__);
+		WARN(1, "%s: sessions DRC could not cache compound\n",
+		     __func__);
 	return;
 }