lavfi/avcodec: deprecate avfilter_fill_frame_from_*_buffer_ref API

Deprecate functions:
avfilter_fill_frame_from_buffer_ref
avfilter_fill_frame_from_audio_buffer_ref
avfilter_fill_frame_from_video_buffer_ref

and schedule to drop them at the next API major bump.

The function avfilter_copy_buf_props() should be used instead.