Fix avisynth compilation after allformats.h was removed

Originally committed as revision 10594 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -793,6 +793,7 @@ audio_beos_demuxer_deps="audio_beos"
 audio_beos_demuxer_extralibs="-lmedia -lbe"
 audio_beos_muxer_deps="audio_beos"
 audio_beos_muxer_extralibs="-lmedia -lbe"
+avisynth_demuxer_deps="avisynth"
 bktr_demuxer_deps_any="dev_bktr_ioctl_bt848_h machine_ioctl_bt848_h dev_video_bktr_ioctl_bt848_h dev_ic_bt8xx_h"
 dv1394_demuxer_deps="dv1394"
 libdc1394_demuxer_deps="libdc1394"

libavformat/allformats.c

@@ -64,9 +64,7 @@ void av_register_all(void)
     REGISTER_MUXDEMUX (AU, au);
     REGISTER_MUXDEMUX (AUDIO_BEOS, audio_beos);
     REGISTER_MUXDEMUX (AVI, avi);
-#ifdef CONFIG_AVISYNTH
-    av_register_input_format(&avisynth_demuxer);
-#endif
+    REGISTER_DEMUXER  (AVISYNTH, avisynth);
     REGISTER_DEMUXER  (AVS, avs);
     REGISTER_DEMUXER  (BETHSOFTVID, bethsoftvid);
     REGISTER_DEMUXER  (BKTR, bktr);