mac80211: use sdata pointer for scan interface

Since we now use sdata pointers most of the time, using a netdev
pointer here is somewhat artificial, use an sdata pointer instead.
Replace a netdev-prefix in a few messages by a wiphy-prefix.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index c68d4df..a33bbd1 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -636,7 +636,7 @@
 	enum { SCAN_SET_CHANNEL, SCAN_SEND_PROBE } scan_state;
 	unsigned long last_scan_completed;
 	struct delayed_work scan_work;
-	struct net_device *scan_dev;
+	struct ieee80211_sub_if_data *scan_sdata;
 	struct ieee80211_channel *oper_channel, *scan_channel;
 	u8 scan_ssid[IEEE80211_MAX_SSID_LEN];
 	size_t scan_ssid_len;