cfg80211: remove enum ieee80211_band

This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/wl3501_cs.c b/drivers/net/wireless/wl3501_cs.c
index d5c371d..99de07d 100644
--- a/drivers/net/wireless/wl3501_cs.c
+++ b/drivers/net/wireless/wl3501_cs.c
@@ -1454,7 +1454,7 @@
 	struct wl3501_card *this = netdev_priv(dev);
 
 	wrqu->freq.m = 100000 *
-		ieee80211_channel_to_frequency(this->chan, IEEE80211_BAND_2GHZ);
+		ieee80211_channel_to_frequency(this->chan, NL80211_BAND_2GHZ);
 	wrqu->freq.e = 1;
 	return 0;
 }