Copy libffi from sxemacs

[Michael Albinus]

Zajcev Evgeny <lg at sxemacs.org> writes:

> dbus is in its very-pre-alpha stage, only one person is working on it
> .. afaik he is the author of GNU Emacsen dbus implementation and tries
> to create compatible bindings using sxemacsen ffi

Hmm, yes. This work is stalled; I shall reactivate it. Unfortunately,
I'll start a business trip end of next week, so it might be delayed
until end of July.

> thanks

Best regards, Michael.