net: hns3: remove unused field 'io_base' in struct hns3_enet_ring

'io_base' has been defined and initialized, but never used,
so remove it.
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns3/hns3_enet.c

@@ -3670,12 +3670,10 @@ static void hns3_ring_get_cfg(struct hnae3_queue *q, struct hns3_nic_priv *priv,
 		ring = &priv->ring[q->tqp_index];
 		desc_num = priv->ae_handle->kinfo.num_tx_desc;
 		ring->queue_index = q->tqp_index;
-		ring->io_base = (u8 __iomem *)q->io_base + HNS3_TX_REG_OFFSET;
 	} else {
 		ring = &priv->ring[q->tqp_index + queue_num];
 		desc_num = priv->ae_handle->kinfo.num_rx_desc;
 		ring->queue_index = q->tqp_index;
-		ring->io_base = q->io_base;
 	}
 
 	hnae3_set_bit(ring->flag, HNAE3_RING_TYPE_B, ring_type);

drivers/net/ethernet/hisilicon/hns3/hns3_enet.h

@@ -380,7 +380,6 @@ struct ring_stats {
 };
 
 struct hns3_enet_ring {
-	u8 __iomem *io_base; /* base io address for the ring */
 	struct hns3_desc *desc; /* dma map address space */
 	struct hns3_desc_cb *desc_cb;
 	struct hns3_enet_ring *next;