orinoco: initiate cfg80211 conversion

Initialise and register a wiphy.

Store the orinoco_private structure in the new wiphy, and use the
net_device private area to store the wireless_dev. This results in a
change to the way we navigate from a net_device to the driver private
orinoco_private, which we encapsulate in the inline function ndev_priv.
Most of the remaining calls to netdev_priv are thus replaced by
ndev_priv.

We can immediately rely on cfg80211 to handle SIOCGIWNAME, so
orinoco_ioctl_getname is removed.

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