add cdvc

(from a patch by Dmitry Vassiliev // slydiman mail ru)

Originally committed as revision 12279 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/riff.c

@@ -88,6 +88,7 @@ const AVCodecTag codec_bmp_tags[] = {
     { CODEC_ID_DVVIDEO, MKTAG('d', 'v', 's', 'l') },
     { CODEC_ID_DVVIDEO, MKTAG('d', 'v', '2', '5') },
     { CODEC_ID_DVVIDEO, MKTAG('d', 'v', '5', '0') },
+    { CODEC_ID_DVVIDEO, MKTAG('c', 'd', 'v', 'c') },    // Canopus DV
     { CODEC_ID_MPEG1VIDEO, MKTAG('m', 'p', 'g', '1') },
     { CODEC_ID_MPEG1VIDEO, MKTAG('m', 'p', 'g', '2') },
     { CODEC_ID_MPEG2VIDEO, MKTAG('m', 'p', 'g', '2') },