net: hns: Remove redundant memset during buffer release

Because all members of desc_cb is assigned when xmit one package, so it
can delete in hnae_free_buffer, as follows:
        - "dma, priv, length, type" are assigned in fill_v2_desc.
        - "page_offset, reuse_flag, buf" are not used in tx direction.
Signed-off-by: Nlipeng <lipeng321@huawei.com>
Signed-off-by: NWeiwei Deng <dengweiwei@huawei.com>
Reviewed-by: NYisen Zhuang <yisen.zhuang@huawei.com>
Signed-off-by: NSalil Mehta <salil.mehta@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns/hnae.c

@@ -61,7 +61,6 @@ static void hnae_free_buffer(struct hnae_ring *ring, struct hnae_desc_cb *cb)
 		dev_kfree_skb_any((struct sk_buff *)cb->priv);
 	else if (unlikely(is_rx_ring(ring)))
 		put_page((struct page *)cb->priv);
-	memset(cb, 0, sizeof(*cb));
 }
 
 static int hnae_map_buffer(struct hnae_ring *ring, struct hnae_desc_cb *cb)