Add constant for AES_KEY_WRAP

[mattburgess]

No description provided.

[bentonstark]

So your code change (except for hsmenums.py) will break all other HSMs. The only HSM vendor that supports CKM_AES_KEY_WRAP based on my recent testing is Cavium. That's why CKM_AES_CBC_PAD is the default option for key wrapping. By changing these functions your solution will work for only Cavium HSMs by default and not work for the majority HSMs. What instead you need to do if you want to alter the code is your last edit which is to add AES_KEY_WRAP to the enumerators. Since Cavium is the outliner, you will need to specify the wrap_key_mech= HsmMech.AES_KEY_WRAP for your calls.

[mattburgess]

Thanks for the quick review. I've pushed a fixup commit to remove the Cavium-specific mech from the wrapping calls.