Hook up the MD studio demuxer and Atrac1 decoder.

Originally committed as revision 19969 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/allcodecs.c

@@ -199,6 +199,7 @@ void avcodec_register_all(void)
     REGISTER_ENCDEC  (AC3, ac3);
     REGISTER_ENCDEC  (ALAC, alac);
     REGISTER_DECODER (APE, ape);
+    REGISTER_DECODER (ATRAC1, atrac1);
     REGISTER_DECODER (ATRAC3, atrac3);
     REGISTER_DECODER (COOK, cook);
     REGISTER_DECODER (DCA, dca);