vlan: update vlan carrier state for admin up/down

	Currently, the VLAN event handler does not adjust the VLAN
device's carrier state when the real device or the VLAN device is set
administratively up or down.

	The following patch adds a transfer of operating state from the
real device to the VLAN device when the real device is administratively
set up or down, and sets the carrier state up or down during init, open
and close of the VLAN device.

	This permits observers above the VLAN device that care about the
carrier state (bonding's link monitor, for example) to receive updates
for administrative changes by more closely mimicing the behavior of real
devices.

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>