Both of these routines are used by 802.11 WPA, but they are generic
and could be needed by other protocols as well.

Signed-off-by: Marty Connor <mdc@etherboot.org>

Add FILE_LICENCE declarations to almost all files that make up the
various standard builds of gPXE.

The various types of cryptographic algorithm are fundamentally
different, and it was probably a mistake to try to handle them via a
single common type.

pubkey_algorithm is a placeholder type for now.