[vlc] compiling vlc with ffmpeg

[Craig Whitmore]

..
> 
> > checking for ffmpeg/avcodec.h... no
> 
> > checking for libavcodec/avcodec.h... yes
> 
> 
> > /* Define to 1 if you have the <ffmpeg/avcodec.h> header file. */
> > /* #undef HAVE_FFMPEG_AVCODEC_H */
> 
> configure says you don't have ffmpeg/avcodec.h so it's good
> you should however have HAVE_LIBAVCODEC_AVCODEC_H defined to 1

the configure makes the config.h file.. even if I change it and rerun
the configure it gets overridden and goes back to not being set.

Thanks