gost28147: simplify internal code
* cipher/gost28147.c (gost_val, _gost_encrypt_data): don't use gost context internally * cipher/gost28147.c (gost_encrypt_block, gost_decrypt_block, _gcry_gost_enc_data): adapt to internal changes.
This saves us one memcpy in _gcry_gost_enc_data(), thus speeding up
GOST R 34.11-94.
- Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>