mac80211: Use a cfg80211_chan_def in ieee80211_hw_conf_chan

Drivers that don't use chanctxes cannot perform VHT association because
they still use a "backward compatibility" pair of {ieee80211_channel,
nl80211_channel_type} in ieee80211_conf and ieee80211_local.

Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
[fix kernel-doc]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/b43/b43.h b/drivers/net/wireless/b43/b43.h
index 10e288d..6a4bd8c 100644
--- a/drivers/net/wireless/b43/b43.h
+++ b/drivers/net/wireless/b43/b43.h
@@ -972,7 +972,7 @@
  */
 static inline enum ieee80211_band b43_current_band(struct b43_wl *wl)
 {
-	return wl->hw->conf.channel->band;
+	return wl->hw->conf.chandef.chan->band;
 }
 
 static inline int b43_bus_may_powerdown(struct b43_wldev *wldev)