isdn: hisax: hfc_usb: use usb_fill_int_urb()

Using usb_fill_int_urb() helps to find code which initializes an
URB. A grep for members of the struct (like ->complete) reveal lots
of other things, too.

The `interval' parameter is now set differently on HS and SS. The
argument is fed from bInterval so it should be the right thing to do.

Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/hisax/hfc_usb.c

@@ -432,16 +432,12 @@ fill_isoc_urb(struct urb *urb, struct usb_device *dev, unsigned int pipe,
 {
 	int k;
 
-	urb->dev = dev;
-	urb->pipe = pipe;
-	urb->complete = complete;
+	usb_fill_int_urb(urb, dev, pipe, buf, packet_size * num_packets,
+			 complete, context, interval);
+
 	urb->number_of_packets = num_packets;
-	urb->transfer_buffer_length = packet_size * num_packets;
-	urb->context = context;
-	urb->transfer_buffer = buf;
 	urb->transfer_flags = URB_ISO_ASAP;
 	urb->actual_length = 0;
-	urb->interval = interval;
 	for (k = 0; k < num_packets; k++) {
 		urb->iso_frame_desc[k].offset = packet_size * k;
 		urb->iso_frame_desc[k].length = packet_size;