wireless: Fix WARN_ON() with ieee802.11b

When the driver registers a IEEE80211_BAND_2GHZ band,
it can either be 802.11b or 802.11g. But when 802.11b rates
are registered "want" will be 3 (since 4 rates are being registered,
and each of those 4 rates will decrease "want").
Since this is a correct situation, there is no need to trigger
a WARN_ON() for this.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

net/wireless/util.c

@@ -80,7 +80,7 @@ static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
 				sband->bitrates[i].flags |=
 					IEEE80211_RATE_ERP_G;
 		}
-		WARN_ON(want != 0 && want != 6);
+		WARN_ON(want != 0 && want != 3 && want != 6);
 		break;
 	case IEEE80211_NUM_BANDS:
 		WARN_ON(1);