avcodec: unschedule removing some functions with FF_API_COPY_CONTEXT

These functions were never deprecated. The merge from commit 6988cf2
included them by mistake.

Found-by: mkver
Signed-off-by: James Almer <[email protected]>

Author: jamrial

libavcodec/avcodec.h

@@ -2770,7 +2770,6 @@ int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
  */
 const AVClass *avcodec_get_class(void);
 
-#if FF_API_COPY_CONTEXT
 /**
  * Get the AVClass for AVFrame. It can be used in combination with
  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
@@ -2787,6 +2786,7 @@ const AVClass *avcodec_get_frame_class(void);
  */
 const AVClass *avcodec_get_subtitle_rect_class(void);
 
+#if FF_API_COPY_CONTEXT
 /**
  * Copy the settings of the source AVCodecContext into the destination
  * AVCodecContext. The resulting destination codec context will be