cfg80211/nl80211: scanning (and mac80211 update to use it)

This patch adds basic scan capability to cfg80211/nl80211 and
changes mac80211 to use it. The BSS list that cfg80211 maintains
is made driver-accessible with a private area in each BSS struct,
but mac80211 doesn't yet use it. That's another large project.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/net/wireless.h b/include/net/wireless.h
index a42c156..1c6285e 100644
--- a/include/net/wireless.h
+++ b/include/net/wireless.h
@@ -213,6 +213,9 @@
 	bool custom_regulatory;
 	bool strict_regulatory;
 
+	int bss_priv_size;
+	u8 max_scan_ssids;
+
 	/* If multiple wiphys are registered and you're handed e.g.
 	 * a regular netdev with assigned ieee80211_ptr, you won't
 	 * know whether it points to a wiphy your driver has registered