lavc: move av_get_pcm_codec() from avcodec.h to codec_id.h

doc/APIchanges

@@ -16,7 +16,8 @@ API changes, most recent first:
 
 2021-xx-xx - xxxxxxxxxx - lavc 59.1.100 - avcodec.h codec_id.h
   Move av_get_bits_per_sample(), av_get_exact_bits_per_sample(),
-  and avcodec_profile_name() from avcodec.h to codec_id.h.
+  avcodec_profile_name(), and av_get_pcm_codec() from avcodec.h
+  to codec_id.h.
 
 2021-xx-xx - xxxxxxxxxx - lavc 59.1.100 - avcodec.h defs.h
   Add new installed header defs.h. The following definitions are moved

libavcodec/avcodec.h

@@ -3111,14 +3111,6 @@ int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
  */
 void avcodec_flush_buffers(AVCodecContext *avctx);
 
-/**
- * Return the PCM codec associated with a sample format.
- * @param be  endianness, 0 for little, 1 for big,
- *            -1 (or anything else) for native
- * @return  AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
- */
-enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
-
 /**
  * Return audio frame duration.
  *

libavcodec/codec_id.h

@@ -22,6 +22,7 @@
 #define AVCODEC_CODEC_ID_H
 
 #include "libavutil/avutil.h"
+#include "libavutil/samplefmt.h"
 
 /**
  * @addtogroup lavc_core
@@ -611,6 +612,14 @@ int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
  */
 const char *avcodec_profile_name(enum AVCodecID codec_id, int profile);
 
+/**
+ * Return the PCM codec associated with a sample format.
+ * @param be  endianness, 0 for little, 1 for big,
+ *            -1 (or anything else) for native
+ * @return  AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
+ */
+enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
+
 /**
  * @}
  */