mt76: mt7921: not support beacon offload disable command

Beacon disable flow would be handled in bss stop handler automatically.
Force return -EOPNOTSUPP in disable case.

Fixes: 116c6960 ("mt76: mt7921: Add AP mode support")
Reviewed-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7921/mcu.c

@@ -981,8 +981,11 @@ mt7921_mcu_uni_add_beacon_offload(struct mt7921_dev *dev,
 	};
 	struct sk_buff *skb;
 
+	/* support enable/update process only
+	 * disable flow would be handled in bss stop handler automatically
+	 */
 	if (!enable)
-		goto out;
+		return -EOPNOTSUPP;
 
 	skb = ieee80211_beacon_get_template(mt76_hw(dev), vif, &offs, 0);
 	if (!skb)
@@ -1008,7 +1011,6 @@ mt7921_mcu_uni_add_beacon_offload(struct mt7921_dev *dev,
 	}
 	dev_kfree_skb(skb);
 
-out:
 	return mt76_mcu_send_msg(&dev->mt76, MCU_UNI_CMD(BSS_INFO_UPDATE),
 				 &req, sizeof(req), true);
 }