Include functionality to support EAP-FAST unconditionally

Include functionality to support EAP-FAST unconditionally

Clean up the internal TLS implementation by removing conditional
build blocks for (mostly) EAP-FAST specific functionality. This
will increase the size a big for non-EAP-FAST builds, but is quite
helpful in making src/tls/libtls.a with single build options. If
the potential size reduction is considered significant in the future,
this can be reconsider with a more library compatible way (e.g.,
external file with registration function, etc.).