The "dev->get_wireless_stats" field is deprecated and slowly
be surely going away. Most drivers have been updated months
ago. Actually, there is an annoying message for driver still using it,
but it seems that user of zd1201 were not annoyed enough ;-)

Signed-off-by: Jean Tourrilhes <jt@hpl.hp.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>