cdc-acm: convert to not directly using urb->status

A step on the road to passing status as a parameter

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/cdc-acm.c

@@ -428,7 +428,7 @@ static void acm_read_bulk_callback(struct urb *urb)
 		return;
 	}
 
-	if (urb->status) {
+	if (status) {
 		set_bit(rb->index, &acm->read_urbs_free);
 		dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
 							__func__, status);
@@ -462,13 +462,14 @@ static void acm_write_bulk(struct urb *urb)
 	struct acm_wb *wb = urb->context;
 	struct acm *acm = wb->instance;
 	unsigned long flags;
+	int status = urb->status;
 
-	if (urb->status	|| (urb->actual_length != urb->transfer_buffer_length))
+	if (status || (urb->actual_length != urb->transfer_buffer_length))
 		dev_vdbg(&acm->data->dev, "%s - len %d/%d, status %d\n",
 			__func__,
 			urb->actual_length,
 			urb->transfer_buffer_length,
-			urb->status);
+			status);
 
 	spin_lock_irqsave(&acm->write_lock, flags);
 	acm_write_done(acm, wb);