mt76: mt76x02u: update ewma pkt len in mt76x02u_tx_prepare_skb

Update ewma packet length in mt76x02u_tx_prepare_skb as it is
done for pci counterpart in order to properly estimate tx time on
current channel
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76x02_usb_core.c

@@ -120,6 +120,12 @@ int mt76x02u_tx_prepare_skb(struct mt76_dev *mdev, void *data,
 	if (!wcid || wcid->hw_key_idx == 0xff || wcid->sw_iv)
 		flags |= MT_TXD_INFO_WIV;
 
+	if (sta) {
+		struct mt76x02_sta *msta = (struct mt76x02_sta *)sta->drv_priv;
+
+		ewma_pktlen_add(&msta->pktlen, tx_info->skb->len);
+	}
+
 	return mt76x02u_skb_dma_info(tx_info->skb, WLAN_PORT, flags);
 }
 EXPORT_SYMBOL_GPL(mt76x02u_tx_prepare_skb);