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.
This adds most of the new frame format and identifier definitions from IEEE
802.11w/D6.0. In addition, the RSN IE capability field values for MFP is
replaced with the new two-bit version with MFPC (capable) and MFPR
(required) processing.
struct wpa_ie_hdr had separate fields for 24-bit OUI and 8-bit oui_type
for WPA/RSN selectors. {WPA,RSN}_SELECTOR_{GET,PUT} access these four
octets through oui and the "out-of-bounds" access for the fourth octet is
actually reading/writing oui_type. This works fine, but some tools complain
about the array bounds "failure". Since oui_type is never accessed
separately, the simplest fix is to just combine these into a single 4-octet
field.