* cipher/ecc-ecdh.c (prepare_ec): Use _gcry_mpi_ec_internal_new.
(_gcry_ecc_mul_point): Don't need to have E of elliptic_curve_t.
* cipher/ecc.c (ecc_encrypt_raw): Use _gcry_mpi_ec_internal_new.
(ecc_decrypt_raw): Likewise.