add XVIX fourcc

[ami_stuff]

add XVIX FourCC as MPEG4 codec (-vcodec mpeg4)

​http://koeln.ccc.de/media/video/Panoptische_Prinzip/DasPanoptischePrinzip_-_SSS2-Lounge.mkv

C:\>ffmpeg -i "C:\DasPanoptischePrinzip_-_SSS2-Lounge.mkv"
FFmpeg version git-N-29181-ga304071, Copyright (c) 2000-2011 the FFmpeg develope
rs
  built on Apr 18 2011 21:24:03 with gcc 4.5.2
  configuration: --enable-gpl --enable-version3 --enable-runtime-cpudetect --ena
ble-memalign-hack --enable-avisynth --enable-bzlib --enable-frei0r --enable-libo
pencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --
enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger
 --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx --enabl
e-libx264 --enable-libxavs --enable-libxvid --enable-zlib --cross-prefix=i686-w6
4-mingw32- --target-os=mingw32 --arch=x86_32 --extra-cflags=-I/home/kyle/softwar
e/ffmpeg/external-libraries/win32/include --extra-ldflags=-L/home/kyle/software/
ffmpeg/external-libraries/win32/lib --pkg-config=pkg-config
  libavutil    50. 40. 1 / 50. 40. 1
  libavcodec   52.120. 0 / 52.120. 0
  libavformat  52.108. 0 / 52.108. 0
  libavdevice  52.  4. 0 / 52.  4. 0
  libavfilter   1. 79. 0 /  1. 79. 0
  libswscale    0. 13. 0 /  0. 13. 0
[matroska,webm @ 01CEC000] Unknown/unsupported CodecID V_MS/VFW/FOURCC.
[matroska,webm @ 01CEC000] max_analyze_duration reached
[matroska,webm @ 01CEC000] Estimating duration from bitrate, this may be inaccur
ate
Input #0, matroska,webm, from 'C:\DasPanoptischePrinzip_-_SSS2-Lounge.mkv':
  Duration: 00:01:58.45, start: 0.000000, bitrate: N/A
    Stream #0.0: Video: XVIX / 0x58495658, 720x576, PAR 1:1 DAR 5:4, 25 fps, 25
tbr, 1k tbn, 25 tbc (default)
    Stream #0.1: Audio: vorbis, 48000 Hz, stereo, s16 (default)
At least one output file must be specified

[Carl Eugen Hoyos]

Fixed in 69cf1824c6001ccc37d9ece5308c9a8f8d1dec26.