then ff_h264_free_tables() and h264_decode_end() can be removed
in h264_decode_init() if it's failed.

The FF_CODEC_CAP_INIT_CLEANUP flag is need for single thread, For multithread,
it'll be cleanup still by AV_CODEC_CAP_FRAME_THREADS flag if have.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Limin Wang <lance.lmwang@gmail.com>