nfsd4: encode_rdattr_error cleanup

static __be32 *

nfsd4_encode_rdattr_error(__be32 *p, int buflen, __be32 nfserr)

{

	__be32 *attrlenp;

	if (buflen < 6)

		return NULL;

	*p++ = htonl(2);

	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */

	*p++ = htonl(0);			 /* bmval1 */

	attrlenp = p++;

	*p++ = htonl(4);     /* attribute length */

	*p++ = nfserr;       /* no htonl */

	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);

	return p;

}