Make STRIBOG use the new _gcry_md_block_write helper
* cipher/stribog.c (STRIBOG_STRUCT): Add 'bctx' and remove 'buf' and 'count'. (stribog_init_512): Initialize 'bctx'. (transform64): New function. (stribog_write): Remove. (stribog_final): Use _gcry_md_block_write and bctx. (_gcry_digest_spec_stribog_256, _gcry_digest_spec_stribog_512): Use _gcry_md_block_write.
- Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>