Support COSE_Mac0

[nodh]

ISO/IEC 18013-5 defines the usage of COSE_Sign1 and COSE_Mac0 objects for device authentication. It defines HMAC 256/256 as the only required algorithm, defines a null payload (i.e. it is detached), and empty external AAD. The MAC key is derived using ECKA-DH (Elliptic Curve Key Agreement Algorithm - Diffie-Hellman) from BSI TR-03111, and Z_AB is used as the ephemeral MAC key. The final MAC Key is derived using HKDF from RFC 5869 with SHA-256.

While we did implement the signature object, we're lacking the support for the MAC object.

[JesusMcCloud]

Timeline:

1. AES (because it introduces MAC)
2. Fix RsaOrHmac Mess
3. ???
4. COSE_Mac0