qlcnic: Fix link speed and duplex display for 83xx adapter

o Set link speed and duplex to unknown when link is not up.

Signed-off-by: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: Shahed Shaikh <shahed.shaikh@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>