cfg80211: Support multiple CSA counters

Change the type of NL80211_ATTR_CSA_C_OFF_BEACON and
NL80211_ATTR_CSA_C_OFF_PRESP to be NLA_BINARY which allows
userspace to use beacons and probe responses with
multiple CSA counters.
This isn't breaking the API since userspace can
continue to use nla_put_u16 for this attributes, which
is equivalent to a single element u16 array.
In addition advertise max number of supported CSA counters.
This is needed when using CSA and eCSA IEs together.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/cfg.c

@@ -3192,8 +3192,14 @@ static int ieee80211_set_csa_beacon(struct ieee80211_sub_if_data *sdata,
 			break;
 
 		sdata->csa_counter_offset_beacon =
-			params->counter_offset_beacon;
-		sdata->csa_counter_offset_presp = params->counter_offset_presp;
+			params->counter_offsets_beacon[0];
+
+		if (params->n_counter_offsets_presp)
+			sdata->csa_counter_offset_presp =
+				params->counter_offsets_presp[0];
+		else
+			sdata->csa_counter_offset_presp = 0;
+
 		err = ieee80211_assign_beacon(sdata, &params->beacon_csa);
 		if (err < 0) {
 			kfree(sdata->u.ap.next_beacon);