Add support for S/PDIF encapsulation.

Originally committed as revision 19674 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/allformats.c

@@ -178,6 +178,7 @@ void av_register_all(void)
     REGISTER_DEMUXER  (SMACKER, smacker);
     REGISTER_DEMUXER  (SOL, sol);
     REGISTER_MUXDEMUX (SOX, sox);
+    REGISTER_MUXER    (SPDIF, spdif);
     REGISTER_DEMUXER  (STR, str);
     REGISTER_MUXDEMUX (SWF, swf);
     REGISTER_MUXER    (TG2, tg2);