text-freetype2: Mark ft2 text source as custom draw

Fixes a bug where the first effect filter on the freetype2 text source
wouldn't be properly applied

plugins/text-freetype2/text-freetype2.c

@@ -34,7 +34,8 @@ uint32_t texbuf_w = 2048, texbuf_h = 2048;
 static struct obs_source_info freetype2_source_info = {
 	.id = "text_ft2_source",
 	.type = OBS_SOURCE_TYPE_INPUT,
-	.output_flags = OBS_SOURCE_VIDEO,
+	.output_flags = OBS_SOURCE_VIDEO |
+	                OBS_SOURCE_CUSTOM_DRAW,
 	.get_name = ft2_source_get_name,
 	.create = ft2_source_create,
 	.destroy = ft2_source_destroy,