dwc_otg: fix potential sleep while atomic during urb enqueue

Fixes a regression introduced with eb1b482. Kmalloc called from
dwc_otg_hcd_qtd_add / dwc_otg_hcd_qtd_create did not always have
the GPF_ATOMIC flag set. Force this flag when inside the larger
critical section.

Author: P33M

drivers/usb/host/dwc_otg/dwc_otg_hcd_linux.c

@@ -781,8 +781,7 @@ static int dwc_otg_urb_enqueue(struct usb_hcd *hcd,
 	{
 		retval = dwc_otg_hcd_urb_enqueue(dwc_otg_hcd, dwc_otg_urb,
 						/*(dwc_otg_qh_t **)*/
-						ref_ep_hcpriv,
-						mem_flags == GFP_ATOMIC ? 1 : 0);
+						ref_ep_hcpriv, 1);
 		if (0 == retval) {
 			if (alloc_bandwidth) {
 				allocate_bus_bandwidth(hcd,