orinoco: Replace net_device with orinoco_private in driver interfaces

orinoco: Replace net_device with orinoco_private in driver interfaces

Move away from using net_device as the main structure in orinoco
function calls. Use orinoco_private instead.

This makes more sense when we move to cfg80211, and we get wiphys as
well.

Signed-off-by: David Kilroy <kilroyd@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>