PM / QoS: Fix a free error in the dev_pm_qos_constraints_destroy()

Free a wrong point to struct dev_pm_qos->latency which suppose to
be the point to struct dev_pm_qos. The patch is to fix the issue.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/qos.c

@@ -253,7 +253,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
 	spin_unlock_irq(&dev->power.lock);
 
 	kfree(c->notifiers);
-	kfree(c);
+	kfree(qos);
 
  out:
 	mutex_unlock(&dev_pm_qos_mtx);