net: mvneta: make mvneta_txq_done() return void

The function return parameter is not used in mvneta_tx_done_gbe(),
where the function is called. This patch makes the function return
void.

Reviewed-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvneta.c

@@ -1314,15 +1314,16 @@ static void mvneta_txq_bufs_free(struct mvneta_port *pp,
 }
 
 /* Handle end of transmission */
-static int mvneta_txq_done(struct mvneta_port *pp,
+static void mvneta_txq_done(struct mvneta_port *pp,
 			   struct mvneta_tx_queue *txq)
 {
 	struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id);
 	int tx_done;
 
 	tx_done = mvneta_txq_sent_desc_proc(pp, txq);
-	if (tx_done == 0)
-		return tx_done;
+	if (!tx_done)
+		return;
+
 	mvneta_txq_bufs_free(pp, txq, tx_done);
 
 	txq->count -= tx_done;
@@ -1331,8 +1332,6 @@ static int mvneta_txq_done(struct mvneta_port *pp,
 		if (txq->size - txq->count >= MAX_SKB_FRAGS + 1)
 			netif_tx_wake_queue(nq);
 	}
-
-	return tx_done;
 }
 
 static void *mvneta_frag_alloc(const struct mvneta_port *pp)