usb: gadget: gr_udc: unconditionally use GFP_ATOMIC in gr_queue_ext()

As far as gr_queue() is called with spinlock held,
we have to pass GFP_ATOMIC regardless of gfp argument.

Found by Linux Driver Verification project (linuxtesting.org).

Acked-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/gr_udc.c b/drivers/usb/gadget/gr_udc.c
index 4966971..99a37ed 100644
--- a/drivers/usb/gadget/gr_udc.c
+++ b/drivers/usb/gadget/gr_udc.c
@@ -1684,7 +1684,7 @@
 	if (ep->is_in)
 		gr_dbgprint_request("EXTERN", ep, req);
 
-	ret = gr_queue(ep, req, gfp_flags);
+	ret = gr_queue(ep, req, GFP_ATOMIC);
 
 	spin_unlock(&ep->dev->lock);