netxen: fix tx descriptor structure

Fix the offset of vlan_TCI field in cmd_desc_type0.

Signed-off-by: Amit Kumar Salecha <amit@qlogic.com>
Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>