cfg80211: show interface type

This patch makes cfg80211 show the interface in the nl80211
information about a specific interface. API users are required
to keep the type updated (everything else is fairly complicated)
but you will get a warning if you fail to keep it updated.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/net/wireless.h

@@ -223,9 +223,11 @@ struct wiphy {
  * the netdev.)
  *
  * @wiphy: pointer to hardware description
+ * @iftype: interface type
  */
 struct wireless_dev {
 	struct wiphy *wiphy;
+	enum nl80211_iftype iftype;
 
 	/* private to the generic wireless code */
 	struct list_head list;