ext/dv/gstdvdec.c: Allow a little margin when negotiating the framerate. Original commit message from CVS: * ext/dv/gstdvdec.c: (gst_dvdec_video_getcaps), (gst_dvdec_video_link), (gst_dvdec_push), (gst_dvdec_loop): Allow a little margin when negotiating the framerate.