This is an initial step in further cleaning up the EAPOL authenticator
use to avoid requiring direct accesses to the internal data structures.
For now, number of external files are still including the internal
definitions from eapol_auth_sm_i.h, but eventually, these direct
references should be removed.
IEEE 802.11w/D6.0 defines new AKMPs to indicate SHA256-based algorithms for
key derivation (and AES-CMAC for EAPOL-Key MIC). Add support for using new
AKMPs and clean up AKMP processing with helper functions in defs.h.
