usb: gadget: Refactor request completion

Use the recently introduced usb_gadget_giveback_request() in favor of
direct invocation of the completion routine.

All places in drivers/usb/ matching "[-.]complete(" were replaced with a
call to usb_gadget_giveback_request(). This was compile-tested with all
ARM drivers enabled and runtime-tested for musb.

Signed-off-by: Michal Sojka <sojka@merica.cz>
Acked-by: Felipe Balbi <balbi@ti.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/udc/pxa27x_udc.c

@@ -758,7 +758,7 @@ static void req_done(struct pxa_ep *ep, struct pxa27x_request *req, int status,
 	if (pflags)
 		spin_unlock_irqrestore(&ep->lock, *pflags);
 	local_irq_save(flags);
-	req->req.complete(&req->udc_usb_ep->usb_ep, &req->req);
+	usb_gadget_giveback_request(&req->udc_usb_ep->usb_ep, &req->req);
 	local_irq_restore(flags);
 	if (pflags)
 		spin_lock_irqsave(&ep->lock, *pflags);