cipher: Add constant for 8 bit CFB mode.
* src/gcrypt.h.in (GCRY_CIPHER_MODE_CFB8): New. * tests/basic.c (check_cfb_cipher): Prepare for CFB-8 tests.
Note that there is no implementation for the 8 bit CFB mode yet. We
will add that as a bug fix after the release of 1.7.0.
- Signed-off-by: Werner Koch <wk@gnupg.org>