net/mlx5: IPSec, Generalize sandbox QP commands

The current code assume only SA QP commands.
Refactor in order to pave the way for new QP commands:
1. Generic cmd response format.
2. SA cmd checks are in dedicated functions.
3. Aligned debug prints.

Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>