net/ncsi: Don't mark configured channels inactive

The concepts of a channel being 'active' and it having link are slightly
muddled in the NCSI driver. Tweak this slightly so that
NCSI_CHANNEL_ACTIVE represents a channel that has been configured and
enabled, and NCSI_CHANNEL_INACTIVE represents a de-configured channel.
This distinction is important because a channel can be 'active' but have
its link down; in this case the channel may still need to be configured
so that it may receive AEN link-state-change packets.

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>