cryptodev: add digest encrypted feature flag

cryptodev: add digest encrypted feature flag

Some PMDs can only support digest being
encrypted separately in auth-cipher operations.
Thus it is required to add feature flag in PMD
to reflect if it does support digest-appended
both: digest generation with encryption and
decryption with digest verification.
This patch also adds information about new
feature flag to the release notes.

Signed-off-by: Damian Nowak <damianx.nowak@intel.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Fiona Trahe <fiona.trahe@intel.com>