lavc: add missing audioconvert includes

libavcodec/mlp_parser.c

@@ -27,6 +27,7 @@
 #include <stdint.h>
 
 #include "libavutil/crc.h"
+#include "libavutil/audioconvert.h"
 #include "get_bits.h"
 #include "parser.h"
 #include "mlp_parser.h"

libavcodec/mpegaudiodec.c

@@ -24,6 +24,7 @@
  * MPEG Audio decoder.
  */
 
+#include "libavutil/audioconvert.h"
 #include "avcodec.h"
 #include "get_bits.h"
 #include "dsputil.h"