mac80211: support spurious class3 event

Add support for the spurious class3 frame event
to mac80211 to enable AP w/o monitor mode.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/rx.c

@@ -866,6 +866,13 @@ ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
 			    rx->sdata->control_port_protocol)
 				return RX_CONTINUE;
 		}
+
+		if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
+		    cfg80211_rx_spurious_frame(rx->sdata->dev,
+					       hdr->addr2,
+					       GFP_ATOMIC))
+			return RX_DROP_UNUSABLE;
+
 		return RX_DROP_MONITOR;
 	}