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/intel/iwlwifi/mvm/rx.c b/drivers/net/wireless/intel/iwlwifi/mvm/rx.c
index d8cadf2..263e8a8 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/rx.c
@@ -319,7 +319,7 @@
 	rx_status->device_timestamp = le32_to_cpu(phy_info->system_timestamp);
 	rx_status->band =
 		(phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_BAND_24)) ?
-				IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
+				NL80211_BAND_2GHZ : NL80211_BAND_5GHZ;
 	rx_status->freq =
 		ieee80211_channel_to_frequency(le16_to_cpu(phy_info->channel),
 					       rx_status->band);