[NET]: Set NLM_F_MULTI in answer of RTM_GETADDR dump answer.

net/ipv4/devinet.c

@@ -922,6 +922,7 @@ static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
 	unsigned char	 *b = skb->tail;
 
 	nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*ifm));
+	if (pid) nlh->nlmsg_flags |= NLM_F_MULTI;
 	ifm = NLMSG_DATA(nlh);
 	ifm->ifa_family = AF_INET;
 	ifm->ifa_prefixlen = ifa->ifa_prefixlen;

net/ipv6/addrconf.c

@@ -2443,6 +2443,7 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
 	unsigned char	 *b = skb->tail;
 
 	nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*ifm));
+	if (pid) nlh->nlmsg_flags |= NLM_F_MULTI;
 	ifm = NLMSG_DATA(nlh);
 	ifm->ifa_family = AF_INET6;
 	ifm->ifa_prefixlen = ifa->prefix_len;