nl80211: Debug print error from airtime weight configuration

It is better to be able to determine whether the airtime weight
configuration for a STA actually was accepted by the driver or not.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/drivers/driver_nl80211.c

@@ -5789,6 +5789,7 @@ static int driver_nl80211_sta_set_airtime_weight(void *priv, const u8 *addr,
 {
 	struct i802_bss *bss = priv;
 	struct nl_msg *msg;
+	int ret;
 
 	wpa_printf(MSG_DEBUG,
 		   "nl80211: Set STA airtime weight - ifname=%s addr=" MACSTR
@@ -5799,7 +5800,13 @@ static int driver_nl80211_sta_set_airtime_weight(void *priv, const u8 *addr,
 	    nla_put_u16(msg, NL80211_ATTR_AIRTIME_WEIGHT, weight))
 		goto fail;
 
-	return send_and_recv_msgs(bss->drv, msg, NULL, NULL, NULL, NULL);
+	ret = send_and_recv_msgs(bss->drv, msg, NULL, NULL, NULL, NULL);
+	if (ret) {
+		wpa_printf(MSG_DEBUG,
+			   "nl80211: SET_STATION[AIRTIME_WEIGHT] failed: ret=%d (%s)",
+			   ret, strerror(-ret));
+	}
+	return ret;
 fail:
 	nlmsg_free(msg);
 	return -ENOBUFS;