PCI: EHCI: Fix crash during hibernation on ASUS computers

Commit dbf0e4c (PCI: EHCI: fix crash during suspend on ASUS
computers) added a workaround for an ASUS suspend issue related to
USB EHCI and a bug in a number of ASUS BIOSes that attempt to shut
down the EHCI controller during system suspend if its PCI command
register doesn't contain 0 at that time.

It turns out that the same workaround is necessary in the analogous
hibernation code path, so add it.

References: https://bugzilla.kernel.org/show_bug.cgi?id=45811
Reported-and-tested-by: Oleksij Rempel <bug-track@fisher-privat.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org

drivers/pci/pci-driver.c

@@ -959,6 +959,13 @@ static int pci_pm_poweroff_noirq(struct device *dev)
 	if (!pci_dev->state_saved && !pci_is_bridge(pci_dev))
 		pci_prepare_to_sleep(pci_dev);
 
+	/*
+	 * The reason for doing this here is the same as for the analogous code
+	 * in pci_pm_suspend_noirq().
+	 */
+	if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI)
+		pci_write_config_word(pci_dev, PCI_COMMAND, 0);
+
 	return 0;
 }