Revert "rtnetlink: Do not generate notifications for CHANGEADDR event"

This reverts commit cd8966e7.

The duplicate CHANGEADDR event message is sent regardless of link
status whereas the setlink changes only generate a notification when
the link is up. Not sending a notification when the link is down breaks
dhcpcd which only processes hwaddr changes when the link is down.

Fixes reported regression:
    https://bugzilla.kernel.org/show_bug.cgi?id=196355Reported-by: Yaroslav Isakov <yaroslav.isakov@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/rtnetlink.c

@@ -4241,6 +4241,7 @@ static int rtnetlink_event(struct notifier_block *this, unsigned long event, voi
 
 	switch (event) {
 	case NETDEV_REBOOT:
+	case NETDEV_CHANGEADDR:
 	case NETDEV_CHANGENAME:
 	case NETDEV_FEAT_CHANGE:
 	case NETDEV_BONDING_FAILOVER: