Relax LV2 plugin filter to substring (e.g. "Utility", "MIDI Utility")

libs/ardour/lv2_plugin.cc

@@ -3356,10 +3356,7 @@ LV2PluginInfo::in_category (const std::string &c) const
 {
 	// TODO use untranslated lilv_plugin_get_class()
 	// match gtk2_ardour/plugin_selector.cc
-	if (category == c) {
-		return true;
-	}
-	return false;
+	return category.find(c) != string::npos;
 }
 
 bool