crypto/aesni_mb: support DES

The Multi-buffer library now supports DES-CBC
and DES-DOCSISBPI algorithms, so this commit
extends adds support for them in the PMD.

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Fan Zhang <roy.fan.zhang@intel.com>
Reviewed-by: Radu Nicolau <radu.nicolau@intel.com>