mac80211: Fix AP mode regression

Commit mac80211: avoid using synchronize_rcu in ieee80211_set_probe_resp
changed the return value when the probe response template is not present.
Revert to the earlier value of 1 - this fixes AP mode for drivers like
ath9k.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/cfg.c

@@ -740,7 +740,7 @@ static int ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata,
 	struct probe_resp *new, *old;
 
 	if (!resp || !resp_len)
-		return -EINVAL;
+		return 1;
 
 	old = rtnl_dereference(sdata->u.ap.probe_resp);