USB: OHCI: fix build error related to ohci_suspend/resume

Commit 9a11899c5e69 (USB: OHCI: add missing PCI PM callbacks to
ohci-pci.c) added missing ohci_suspend and ohci_resume callback
pointers, but forgot that these callbacks are declared and defined
only when CONFIG_PM is enabled.

This patch adds a preprocessor conditional to avoid build errors when
PM is disabled.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Meelis Roos <mroos@linux.ee>,
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ohci-pci.c

@@ -305,9 +305,11 @@ static int __init ohci_pci_init(void)
 
 	ohci_init_driver(&ohci_pci_hc_driver, &pci_overrides);
 
+#ifdef	CONFIG_PM
 	/* Entries for the PCI suspend/resume callbacks are special */
 	ohci_pci_hc_driver.pci_suspend = ohci_suspend;
 	ohci_pci_hc_driver.pci_resume = ohci_resume;
+#endif
 
 	return pci_register_driver(&ohci_pci_driver);
 }