usb:hub set hub->change_bits when over-current happens

When we are doing compliance test with xHCI, we found that if we
enable CONFIG_USB_SUSPEND and plug in a bad device which causes
over-current condition to the root port, software will not be noticed.
The reason is that current code don't set hub->change_bits in
hub_activate() when over-current happens, and then hub_events() will
not check the port status because it thinks nothing changed.
If CONFIG_USB_SUSPEND is disabled, the interrupt pipe of the hub will
report the change and set hub->event_bits, and then hub_events() will
check what events happened.In this case over-current can be detected.

Signed-off-by: Shen Guang <shenguang10@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hub.c

@@ -1147,7 +1147,8 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
 			/* Tell khubd to disconnect the device or
 			 * check for a new connection
 			 */
-			if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
+			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
+			    (portstatus & USB_PORT_STAT_OVERCURRENT))
 				set_bit(port1, hub->change_bits);
 
 		} else if (portstatus & USB_PORT_STAT_ENABLE) {