[MPlayer-DOCS] update english mplayer man page: removed -lavcopts acodec=mp3

[A C Hurst]

> >+MPEG Layer 3 (we encourage you to use -oac mp3lame and -lameopts
> >instead)
> 
> why is this encouraged one way or the other? just curious... 
> 
> only thing i remember is lavcopts acodec=faac is better than -oac faac
> for quicktime-compatable files.

I think it's just because quite a few more options are available using oac mp3lame, through
lameopts.
You're restricted (I think - correct me if I'm wrong) that only the standard lavcopts are available
if you use libmp3lame through lavc.

Also libavcodec is ffmpeg territory. =)

Andy