isdn: l3ni1: Fix set-but-unused variables.

The variable 'cause' is set but unused in ni1up().  Just
kill it off.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/isdn/hisax/l3ni1.c b/drivers/isdn/hisax/l3ni1.c
index 7b229c0..092dcbb 100644
--- a/drivers/isdn/hisax/l3ni1.c
+++ b/drivers/isdn/hisax/l3ni1.c
@@ -2883,7 +2883,7 @@
 static void
 ni1up(struct PStack *st, int pr, void *arg)
 {
-	int i, mt, cr, cause, callState;
+	int i, mt, cr, callState;
 	char *ptr;
 	u_char *p;
 	struct sk_buff *skb = arg;
@@ -2986,12 +2986,10 @@
 				return;
 			}
 		} else if (mt == MT_STATUS) {
-			cause = 0;
 			if ((ptr = findie(skb->data, skb->len, IE_CAUSE, 0)) != NULL) {
 				ptr++;
 				if (*ptr++ == 2)
 					ptr++;
-				cause = *ptr & 0x7f;
 			}
 			callState = 0;
 			if ((ptr = findie(skb->data, skb->len, IE_CALL_STATE, 0)) != NULL) {