The functions ifx_deu_aes_cfg and ifx_deu_aes_ofb have been part of the
driver ever since. But the functions and definitions to make the
algorithms actually usable were missing.
This patch adds the neccessary code for aes_ofb and aes_cfb algorithms.

Signed-off-by: Daniel Kestrel <kestrel1974@t-online.de>