kdf: Fix computation by big-endian machine.
* cipher/kdf.c (beswap64_block): New. (argon2_fill_first_blocks): Convert to native endian. (pseudo_random_generate): Run in native endian. (argon2_compute_segment): Run in native endian. (argon2_final): Convert from native endian.
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>