avcodec.h: split AVCodec API into its own header

doc/APIchanges

@@ -15,6 +15,9 @@ libavutil:     2017-10-21
 
 API changes, most recent first:
 
+2020-xx-xx - xxxxxxxxxx - lavc 58.88.100 - avcodec.h codec.h
+  Move AVCodec-related public API to new header codec.h.
+
 2020-05-23 - xxxxxxxxxx - lavu 56.49.100 - video_enc_params.h
   Add AV_VIDEO_ENC_PARAMS_H264.
 

libavcodec/Makefile

@@ -7,6 +7,7 @@ HEADERS = ac3_parser.h                                                  \
           avdct.h                                                       \
           avfft.h                                                       \
           bsf.h                                                         \
+          codec.h                                                       \
           codec_desc.h                                                  \
           codec_id.h                                                    \
           codec_par.h                                                   \

libavcodec/version.h

@@ -28,8 +28,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVCODEC_VERSION_MAJOR  58
-#define LIBAVCODEC_VERSION_MINOR  87
-#define LIBAVCODEC_VERSION_MICRO 101
+#define LIBAVCODEC_VERSION_MINOR  88
+#define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \