test: mark the synaptics clickpad as buttonpad

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Jonas Ådahl <jadahl@gmail.com>

test/litest-synaptics.c

@@ -79,6 +79,8 @@ static int events[] = {
 	EV_KEY, BTN_TOOL_DOUBLETAP,
 	EV_KEY, BTN_TOOL_TRIPLETAP,
 	EV_KEY, BTN_TOOL_QUADTAP,
+	INPUT_PROP_MAX, INPUT_PROP_POINTER,
+	INPUT_PROP_MAX, INPUT_PROP_BUTTONPAD,
 	-1, -1,
 };