net: dm9051: Fix missing dev_kfree_skb() in dm9051_loop_rx()

The dm9051_loop_rx() returns without release skb when dm9051_stop_mrcmd()
returns error, free the skb to avoid this leak.

Fixes: 2dc95a4d30 ("net: Add dm9051 driver")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/davicom/dm9051.c

@@ -798,8 +798,10 @@ static int dm9051_loop_rx(struct board_info *db)
 		}
 
 		ret = dm9051_stop_mrcmd(db);
-		if (ret)
+		if (ret) {
+			dev_kfree_skb(skb);
 			return ret;
+		}
 
 		skb->protocol = eth_type_trans(skb, db->ndev);
 		if (db->ndev->features & NETIF_F_RXCSUM)