avcodec/ylc: Remove inclusion of huffyuvdsp.h

Also improve the other headers a bit.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/ylc.c

@@ -18,21 +18,17 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
 
 #define YLC_VLC_BITS 10
 
-#include "libavutil/imgutils.h"
-#include "libavutil/internal.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mem.h"
+#include "libavutil/pixfmt.h"
 #include "avcodec.h"
 #include "bswapdsp.h"
 #include "codec_internal.h"
 #include "get_bits.h"
-#include "huffyuvdsp.h"
 #include "thread.h"
 #include "unary.h"