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/net/mac80211/iface.c b/net/mac80211/iface.c
index 097ece8..6a33f0b 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1800,7 +1800,7 @@
 	INIT_DELAYED_WORK(&sdata->dec_tailroom_needed_wk,
 			  ieee80211_delayed_tailroom_dec);
 
-	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+	for (i = 0; i < NUM_NL80211_BANDS; i++) {
 		struct ieee80211_supported_band *sband;
 		sband = local->hw.wiphy->bands[i];
 		sdata->rc_rateidx_mask[i] =