avfilter/vf_vflip: Remove empty options and AVClass

This filter only had an AVClass and empty options because up until
recently, avfilter_init_str() errored out when options were provided
for a filter without an AVClass. But setting (generic) options is
necessary to take advantage of timeline support. So with
avfilter_init_str() fixed, the AVClass and the options can be removed.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavfilter/vf_vflip.c

@@ -24,24 +24,16 @@
  */
 
 #include "libavutil/internal.h"
-#include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "video.h"
 
 typedef struct FlipContext {
-    const AVClass *class;
     int vsub;   ///< vertical chroma subsampling
     int bayer;
 } FlipContext;
 
-static const AVOption vflip_options[] = {
-    { NULL }
-};
-
-AVFILTER_DEFINE_CLASS(vflip);
-
 static int config_input(AVFilterLink *link)
 {
     FlipContext *flip = link->dst->priv;
@@ -139,7 +131,6 @@ const AVFilter ff_vf_vflip = {
     .name        = "vflip",
     .description = NULL_IF_CONFIG_SMALL("Flip the input video vertically."),
     .priv_size   = sizeof(FlipContext),
-    .priv_class  = &vflip_class,
     FILTER_INPUTS(avfilter_vf_vflip_inputs),
     FILTER_OUTPUTS(ff_video_default_filterpad),
     .flags       = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,