lavfi/ocv: make use of AVFILTER_DEFINE_CLASS

Signed-off-by: Paul B Mahol <onemda@gmail.com>

libavfilter/vf_libopencv.c

@@ -378,18 +378,13 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 
 #define OFFSET(x) offsetof(OCVContext, x)
 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
-static const AVOption options[] = {
+static const AVOption ocv_options[] = {
     { "filter_name",   NULL, OFFSET(name),   AV_OPT_TYPE_STRING, .flags = FLAGS },
     { "filter_params", NULL, OFFSET(params), AV_OPT_TYPE_STRING, .flags = FLAGS },
     { NULL },
 };
 
-static const AVClass ocv_class = {
-    .class_name = "ocv",
-    .item_name  = av_default_item_name,
-    .option     = options,
-    .version    = LIBAVUTIL_VERSION_INT,
-};
+AVFILTER_DEFINE_CLASS(ocv);
 
 static const AVFilterPad avfilter_vf_ocv_inputs[] = {
     {