crypto/qat: fix DOCSIS performance

crypto/qat: fix DOCSIS performance

DOCSIS protocol performance in the downlink direction can be improved
significantly in the QAT SYM PMD, especially for larger packets, by
pre-processing all CRC generations in a batch before building and
enqueuing any requests to the HW. This patch adds this optimization.

Fixes: 6f0ef237404b ("crypto/qat: support DOCSIS protocol")
Signed-off-by: David Coyle <david.coyle@intel.com>
Acked-by: Fiona Trahe <fiona.trahe@intel.com>