Input: synaptics-rmi4 - do not check for NULL when calling of_node_put()

The of_node_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/rmi4/rmi_bus.c

···
 void rmi_unregister_function(struct rmi_function *fn)
 {
 	device_del(&fn->dev);
-
-	if (fn->dev.of_node)
-		of_node_put(fn->dev.of_node);
-
+	of_node_put(fn->dev.of_node);
 	put_device(&fn->dev);
 }