* pgp.h: Include bignum.h, don't pretend to work without bignums.

* pgp-encode.c (pgp_put_mpi, pgp_put_public_rsa_key)
(pgp_put_rsa_sha1_signature): Define unconditionally. Removed the
checking of HAVE_LIBGMP and WITH_PUBLIC_KEY.

Rev: nettle/pgp-encode.c:1.2
Rev: nettle/pgp.h:1.2