isdn: gigaset: Fix set-but-unused variable.

The variable 'offset' is set but unused in
write_iso_tasklet().  Just kill it off.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/isdn/gigaset/bas-gigaset.c b/drivers/isdn/gigaset/bas-gigaset.c
index 8a3c5cf..3913f47 100644
--- a/drivers/isdn/gigaset/bas-gigaset.c
+++ b/drivers/isdn/gigaset/bas-gigaset.c
@@ -1157,7 +1157,6 @@
 	struct urb *urb;
 	int status;
 	struct usb_iso_packet_descriptor *ifd;
-	int offset;
 	unsigned long flags;
 	int i;
 	struct sk_buff *skb;
@@ -1225,7 +1224,6 @@
 			 *   successfully sent
 			 * - all following frames are not sent at all
 			 */
-			offset = done->limit;	/* default (no error) */
 			for (i = 0; i < BAS_NUMFRAMES; i++) {
 				ifd = &urb->iso_frame_desc[i];
 				if (ifd->status ||
@@ -1235,9 +1233,6 @@
 						 i, ifd->actual_length,
 						 ifd->length,
 						 get_usb_statmsg(ifd->status));
-					offset = (ifd->offset +
-						  ifd->actual_length)
-						 % BAS_OUTBUFSIZE;
 					break;
 				}
 			}