avcodec/dca_core: Remove unneeded emms.h inclusion

Possible since 7ec2354c.
Reviewed-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavcodec/dca_core.c

@@ -19,7 +19,6 @@
  */
 
 #include "libavutil/channel_layout.h"
-#include "libavutil/emms.h"
 #include "dcaadpcm.h"
 #include "dcadec.h"
 #include "dcadata.h"