File ffmpeg-prefer-dav1d-for-playback.patch of Package ffmpeg-4

--- ffmpeg/libavcodec/allcodecs.c	2019-03-18 20:18:37.438255620 +0100
+++ ffmpeg-patched/libavcodec/allcodecs.c	2019-03-18 21:35:10.699559247 +0100
@@ -675,13 +675,13 @@
 extern AVCodec ff_pcm_mulaw_at_decoder;
 extern AVCodec ff_qdmc_at_decoder;
 extern AVCodec ff_qdm2_at_decoder;
+extern AVCodec ff_libdav1d_decoder;
 extern AVCodec ff_libaom_av1_decoder;
 extern AVCodec ff_libaom_av1_encoder;
 extern AVCodec ff_libaribb24_decoder;
 extern AVCodec ff_libcelt_decoder;
 extern AVCodec ff_libcodec2_encoder;
 extern AVCodec ff_libcodec2_decoder;
-extern AVCodec ff_libdav1d_decoder;
 extern AVCodec ff_libdavs2_decoder;
 extern AVCodec ff_libfdk_aac_encoder;
 extern AVCodec ff_libfdk_aac_decoder;