Update for alloc_buffer changes.

Update for alloc_buffer changes.

Original commit message from CVS:
2005-12-05  Andy Wingo  <wingo@pobox.com>

* ext/dv/gstdvdec.c: (gst_dvdec_chain):
* ext/flac/gstflacdec.c: (gst_flacdec_write):
* ext/flac/gstflacenc.c: (gst_flacenc_write_callback):
* ext/gdk_pixbuf/gstgdkpixbuf.c: (gst_gdk_pixbuf_chain):
* ext/gdk_pixbuf/pixbufscale.c: (gst_pixbufscale_chain):
* ext/jpeg/gstjpegdec.c: (gst_jpeg_dec_chain):
* ext/jpeg/gstjpegenc.c: (gst_jpegenc_chain):
* ext/ladspa/gstsignalprocessor.c: (gst_signal_processor_process):
* ext/libpng/gstpngdec.c: (user_info_callback), (gst_pngdec_task):
* ext/speex/gstspeexdec.c: (speex_dec_chain):
* ext/speex/gstspeexenc.c: (gst_speexenc_chain):
* gst/auparse/gstauparse.c: (gst_auparse_chain):
* gst/flx/gstflxdec.c: (gst_flxdec_chain):
* gst/goom/gstgoom.c: (gst_goom_chain):
* gst/matroska/matroska-demux.c:
(gst_matroska_demux_push_vorbis_codec_priv_data),
(gst_matroska_demux_add_wvpk_header):
* gst/multipart/multipartdemux.c: (gst_multipart_demux_chain):
* gst/multipart/multipartmux.c: (gst_multipart_mux_collected):
* gst/videomixer/videomixer.c: (gst_videomixer_collected):
* gst/wavenc/gstwavenc.c: (gst_wavenc_chain): Update for
alloc_buffer changes.