add 4xm to the family

Originally committed as revision 1904 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/allformats.c

@@ -47,6 +47,7 @@ void av_register_all(void)
     mov_init();
     jpeg_init();
     dv_init();
+    fourxm_init();
 
     av_register_output_format(&yuv4mpegpipe_oformat);
     

libavformat/avformat.h

@@ -329,6 +329,9 @@ int ffm_init(void);
 extern AVInputFormat redir_demux;
 int redir_open(AVFormatContext **ic_ptr, ByteIOContext *f);
 
+/* 4xm.c */
+int fourxm_init(void);
+
 #include "rtp.h"
 
 #include "rtsp.h"