dpxenc: Don't include the libavcodec ident if bitexact mode is enabled

This avoids breaking fate every time the lavc version is bumped.
Signed-off-by: Martin Storsjö <martin@martin.st>

libavcodec/dpxenc.c

@@ -126,7 +126,8 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     memcpy (buf +   8, "V1.0", 4);
     write32(buf +  20, 1); /* new image */
     write32(buf +  24, HEADER_SIZE);
-    memcpy (buf + 160, LIBAVCODEC_IDENT, FFMIN(sizeof(LIBAVCODEC_IDENT), 100));
+    if (!(avctx->flags & CODEC_FLAG_BITEXACT))
+        memcpy (buf + 160, LIBAVCODEC_IDENT, FFMIN(sizeof(LIBAVCODEC_IDENT), 100));
     write32(buf + 660, 0xFFFFFFFF); /* unencrypted */
 
     /* Image information header */

tests/ref/lavf/dpx

-5bb43eae2d80da95d26f7fe4669d6166 *./tests/data/images/dpx/02.dpx
+808ea110635774252439722a48329d61 *./tests/data/images/dpx/02.dpx
 ./tests/data/images/dpx/%02d.dpx CRC=0x6da01946
 305792 ./tests/data/images/dpx/02.dpx