simple_kexinit. Don't inherit make_kexinit.
(make_kexinit_info): Renamed from make_simple_kexinit.
(make_kexinit): New function, replacing the make method of
the make_kexinit class.

* src/keyexchange.h (class make_kexinit): Deleted abstract class.

Rev: src/keyexchange.c:1.102
Rev: src/keyexchange.h:1.63