net: vertexcom: mse102x: Fix tx_bytes calculation

The tx_bytes should consider the actual size of the Ethernet frames
without the SPI encapsulation. But we still need to take care of
Ethernet padding.

Fixes: 2f207cb ("net: vertexcom: Add MSE102x SPI support")
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://patch.msgid.link/20241108114343.6174-3-wahrenst@gmx.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: lategoodbye

drivers/net/ethernet/vertexcom/mse102x.c

@@ -437,13 +437,15 @@ static void mse102x_tx_work(struct work_struct *work)
 	mse = &mses->mse102x;
 
 	while ((txb = skb_dequeue(&mse->txq))) {
+		unsigned int len = max_t(unsigned int, txb->len, ETH_ZLEN);
+
 		mutex_lock(&mses->lock);
 		ret = mse102x_tx_pkt_spi(mse, txb, work_timeout);
 		mutex_unlock(&mses->lock);
 		if (ret) {
 			mse->ndev->stats.tx_dropped++;
 		} else {
-			mse->ndev->stats.tx_bytes += txb->len;
+			mse->ndev->stats.tx_bytes += len;
 			mse->ndev->stats.tx_packets++;
 		}