Missing header file from gcc

[Ollivier Robert]

According to Ollivier Robert:
> The build fails with the following at link stage:

Let's call it library pollution. Removing the previous ffmpeg package
before rebuilding the new one « fixes » the problem.
-- 
Ollivier ROBERT -=- FreeBSD: The Power to Serve! -=- roberto at keltia.freenix.fr
Darwin snuadh.freenix.org Kernel Version 7.0.0: Wed Sep 24 15:48:39 PDT 2003