Fix regression with 'ip address show'

Fix regression with 'ip address show'

`ip a s` no longer shows addresses since 3.4.0 works, but 3.5.0,

the simple test case:
make clean && make -j -s && ./ip/ip a s lo

before that change, i would get:
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever

but after, i now get:
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

seems like the bug was introduced in the middle of that patch:

-	if (filter.family != AF_PACKET) {
+	if (filter.family && filter.family != AF_PACKET) {
+		if (filter.oneline)
+			no_link = 1;
+
 		if (rtnl_wilddump_request(&rth, filter.family, RTM_GETADDR) < 0) {
 			perror("Cannot send dump request");
 			exit(1);

if i revert the change to the if statement there, `ip a s` works for me again.