This adds EAP-TNC method and TNCS (IF-IMV and IF-TNCCS) functionality.
There is no integration with EAP-TTLS and EAP-FAST at this point, so this
version is not yet suitable for real use (i.e., EAP-TNC can only be tested
outside a tunnel which is not an allowed configuration for deployment).
However, the basic TNCS functionality is more or less complete and this
version seems to interoperate with wpa_supplicant.
Number of TLVs were processed in groups and these cases were now separated
into more flexible processing of one TLV at the time. wpabuf_concat()
function was added to make it easier to concatenate TLVs. EAP Sequences are
now supported in both server and peer code, but the server side is not
enabled by default.
This allows Phase 2 Identity Request to be skipped if the identity is
already known from PAC-Opaque received in TLS handshake in order to save
one roundtrip from normal authentication.
