Merge ffmpeg fix for sagetv recordings from upstream
> commit c071b006436d663b977068f8d23cbc061f40491f
> Author: Michael Niedermayer <michaelni@gmx.at>
> Date:   Mon Jan 21 04:21:56 2013 +0100
>
>     mpeg12demux: Fallback to startcode for stream type identification.
>
>    Fixes Ticket2147
>    Fixes SageTV support
>
>    Based-on patch by Andrew Gallatin
>    Signed-off-by: Michael Niedermayer <michaelni@gmx.at>