PCI: PM: Fix ordering of operations in pci_back_from_sleep()

The ordering of operations in pci_back_from_sleep() is incorrect,
because the device may be in D3cold when it runs and pci_enable_wake()
needs to access the device's configuration space which cannot be
done in D3cold.

Fix this by calling pci_set_power_state() to put the device into D0
before calling pci_enable_wake() for it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pci.c

@@ -2638,8 +2638,13 @@ EXPORT_SYMBOL(pci_prepare_to_sleep);
  */
 int pci_back_from_sleep(struct pci_dev *dev)
 {
+	int ret = pci_set_power_state(dev, PCI_D0);
+
+	if (ret)
+		return ret;
+
 	pci_enable_wake(dev, PCI_D0, false);
-	return pci_set_power_state(dev, PCI_D0);
+	return 0;
 }
 EXPORT_SYMBOL(pci_back_from_sleep);