PCI: fix incorrect error return in pci_enable_wake

This patch (as1186) fixes a minor mistake in pci_enable_wake().  When
the routine is asked to disable remote wakeup, it should not return an
error merely because the device is not allowed to do wakeups!

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/pci.c

@@ -1091,7 +1091,7 @@ int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
 	int error = 0;
 	bool pme_done = false;
 
-	if (!device_may_wakeup(&dev->dev))
+	if (enable && !device_may_wakeup(&dev->dev))
 		return -EINVAL;
 
 	/*