Set bits_per_raw_sample appropriately in dpx decoder.

Originally committed as revision 20887 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/dpx.c

@@ -92,6 +92,7 @@ static int decode_frame(AVCodecContext *avctx,
 
     // Need to end in 0x323 to read the bits per color
     buf += 3;
+    avctx->bits_per_raw_sample =
     bits_per_color = buf[0];
 
     switch (descriptor) {