Input: psmouse - fix input_dev leak in lifebook driver

The lifebook driver may register a second input device, but it never
unregisters it.  This fixes that.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/mouse/lifebook.c b/drivers/input/mouse/lifebook.c
index 9ec57d8..df81b0a 100644
--- a/drivers/input/mouse/lifebook.c
+++ b/drivers/input/mouse/lifebook.c
@@ -225,8 +225,13 @@
 
 static void lifebook_disconnect(struct psmouse *psmouse)
 {
+	struct lifebook_data *priv = psmouse->private;
+
 	psmouse_reset(psmouse);
-	kfree(psmouse->private);
+	if (priv) {
+		input_unregister_device(priv->dev2);
+		kfree(priv);
+	}
 	psmouse->private = NULL;
 }