bonding: NS target should accept link local address

When setting bond NS target, we use bond_is_ip6_target_ok() to check
if the address valid. The link local address was wrongly rejected in
bond_changelink(), as most time the user just set the ARP/NS target to
gateway, while the IPv6 gateway is always a link local address when user
set up interface via SLAAC.

So remove the link local addr check when setting bond NS target.

Fixes: 129e3c1b ("bonding: add new option ns_ip6_target")
Reported-by: NLi Liang <liali@redhat.com>
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Reviewed-by: NJonathan Toppins <jtoppins@redhat.com>
Acked-by: NJay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_netlink.c

@@ -290,11 +290,6 @@ static int bond_changelink(struct net_device *bond_dev, struct nlattr *tb[],
 
 			addr6 = nla_get_in6_addr(attr);
 
-			if (ipv6_addr_type(&addr6) & IPV6_ADDR_LINKLOCAL) {
-				NL_SET_ERR_MSG(extack, "Invalid IPv6 addr6");
-				return -EINVAL;
-			}
-
 			bond_opt_initextra(&newval, &addr6, sizeof(addr6));
 			err = __bond_opt_set(bond, BOND_OPT_NS_TARGETS,
 					     &newval);