USB: remove fake "address-of" expressions

Fake "address-of" expressions that evaluate to NULL generally confuse
readers and can provoke compiler warnings.  This patch (as1412)
removes three such fake expressions, using "#ifdef"s in their place.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/driver.c

@@ -1791,15 +1791,13 @@ static const struct dev_pm_ops usb_bus_pm_ops = {
 	.runtime_idle =		usb_runtime_idle,
 };
 
-#else
-
-#define usb_bus_pm_ops	(*(const struct dev_pm_ops *) NULL)
-
 #endif /* CONFIG_USB_SUSPEND */
 
 struct bus_type usb_bus_type = {
 	.name =		"usb",
 	.match =	usb_device_match,
 	.uevent =	usb_uevent,
+#ifdef CONFIG_USB_SUSPEND
 	.pm =		&usb_bus_pm_ops,
+#endif
 };