avutil: bump version after addition of av_sat_add64 and av_sat_sub64

Signed-off-by: James Almer <jamrial@gmail.com>

doc/APIchanges

@@ -15,6 +15,9 @@ libavutil:     2017-10-21
 
 API changes, most recent first:
 
+2020-05-xx - xxxxxxxxxx - lavu 56.46.100 - common.h
+  Add av_sat_add64() and av_sat_sub64()
+
 2020-xx-xx - xxxxxxxxxx - lavu 56.45.100 - video_enc_params.h
                           lavc 58.84.100 - avcodec.h
   Add a new API for exporting video encoding information.

libavutil/version.h

@@ -79,7 +79,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  56
-#define LIBAVUTIL_VERSION_MINOR  45
+#define LIBAVUTIL_VERSION_MINOR  46
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \