wireless: fix CFG80211_WEXT build problems

Fix CFG80211_WEXT build dependencies/errors:

ERROR: "cfg80211_wext_siwscan" [drivers/net/wireless/orinoco/orinoco.ko] undefined!
ERROR: "cfg80211_wext_siwmode" [drivers/net/wireless/orinoco/orinoco.ko] undefined!
ERROR: "cfg80211_wext_giwrange" [drivers/net/wireless/orinoco/orinoco.ko] undefined!
ERROR: "cfg80211_wext_giwmode" [drivers/net/wireless/orinoco/orinoco.ko] undefined!
ERROR: "cfg80211_wext_giwname" [drivers/net/wireless/orinoco/orinoco.ko] undefined!
ERROR: "cfg80211_wext_giwscan" [drivers/net/wireless/orinoco/orinoco.ko] undefined!
ERROR: "cfg80211_wext_giwname" [drivers/net/wireless/ipw2x00/ipw2200.ko] undefined!

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>