net: arp: use assignment

Only when dont_send is 0, arp_filter() is consulted, so we can simply
assign the return value of arp_filter() to dont_send instead.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/arp.c

@@ -883,7 +883,7 @@ static int arp_process(struct sk_buff *skb)
 
 			dont_send = arp_ignore(in_dev, sip, tip);
 			if (!dont_send && IN_DEV_ARPFILTER(in_dev))
-				dont_send |= arp_filter(sip, tip, dev);
+				dont_send = arp_filter(sip, tip, dev);
 			if (!dont_send) {
 				n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
 				if (n) {