test/crypto: add combined mode IPsec cases

test/crypto: add combined mode IPsec cases

Add framework to test IPsec features with all supported
combinations of ciphers.

Combined mode tests are used to test all IPsec features against all
ciphers supported by the PMD. The framework is introduced to avoid
testing with any specific algo, thereby making it mandatory to be
supported. Also, testing with all supported combinations will help with
increasing coverage as well.

The tests would first do IPsec encapsulation and do sanity checks. Based
on flags, packet would be updated or additional checks are done,
followed by IPsec decapsulation. Since the encrypted packet is generated
by the test, known vectors are not required.

Signed-off-by: Anoob Joseph <anoobj@marvell.com>
Signed-off-by: Tejasree Kondoj <ktejasree@marvell.com>
Acked-by: Akhil Goyal <gakhil@marvell.com>
Acked-by: Ciara Power <ciara.power@intel.com>