automatically remove mess

Originally committed as revision 4529 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/avcodec.h

@@ -1885,7 +1885,9 @@ typedef struct AVCodec {
     int (*decode)(AVCodecContext *, void *outdata, int *outdata_size,
                   uint8_t *buf, int buf_size);
     int capabilities;
+#if LIBAVCODEC_VERSION_INT < ((50<<16)+(0<<8)+0)
     void *dummy; // FIXME remove next time we break binary compatibility
+#endif
     struct AVCodec *next;
     void (*flush)(AVCodecContext *);
     const AVRational *supported_framerates; ///array of supported framerates, or NULL if any, array is terminated by {0,0}