mac80211: send AP probe as unicast again

Louis reported that a static checker was complaining that
the 'dst' variable was set (multiple times) but not used.
This is due to a previous commit having removed the usage
(apparently erroneously), so add it back.

Fixes: a344d6778a98 ("mac80211: allow drivers to support NL80211_SCAN_FLAG_RANDOM_ADDR")
Reported-by: Louis Langholtz <lou_langholtz@me.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mlme.c

@@ -2233,7 +2233,7 @@ static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
 		else
 			ssid_len = ssid[1];
 
-		ieee80211_send_probe_req(sdata, sdata->vif.addr, NULL,
+		ieee80211_send_probe_req(sdata, sdata->vif.addr, dst,
 					 ssid + 2, ssid_len, NULL,
 					 0, (u32) -1, true, 0,
 					 ifmgd->associated->channel, false);