usb: chipidea: Drop lock across event_notify during gadget stop

The CI_HDRC_CONTROLLER_STOPPED_EVENT may want to call sleeping
APIs similar to how _gadget_stop_activity() may. Let's drop the
lock across the event so that glue drivers can make sleeping
calls.

Cc: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NStephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: NPeter Chen <peter.chen@nxp.com>

drivers/usb/chipidea/udc.c

@@ -1793,10 +1793,10 @@ static int ci_udc_stop(struct usb_gadget *gadget)
 
 	if (ci->vbus_active) {
 		hw_device_state(ci, 0);
+		spin_unlock_irqrestore(&ci->lock, flags);
 		if (ci->platdata->notify_event)
 			ci->platdata->notify_event(ci,
 			CI_HDRC_CONTROLLER_STOPPED_EVENT);
-		spin_unlock_irqrestore(&ci->lock, flags);
 		_gadget_stop_activity(&ci->gadget);
 		spin_lock_irqsave(&ci->lock, flags);
 		pm_runtime_put(&ci->gadget.dev);