NFSD: add encoding of op_recall flag for write delegation

Modified nfsd4_encode_open to encode the op_recall flag properly
for OPEN result with write delegation granted.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org

fs/nfsd/nfs4xdr.c

@@ -3970,7 +3970,7 @@ nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr,
 		p = xdr_reserve_space(xdr, 32);
 		if (!p)
 			return nfserr_resource;
-		*p++ = cpu_to_be32(0);
+		*p++ = cpu_to_be32(open->op_recall);
 
 		/*
 		 * TODO: space_limit's in delegations