sfc: Use 'skb_add_rx_frag()' instead of hand coding it

Some lines of code can be merged into an equivalent 'skb_add_rx_frag()'
call which is less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sfc/rx.c

@@ -94,12 +94,11 @@ static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
 		rx_buf->len -= hdr_len;
 
 		for (;;) {
-			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
-					   rx_buf->page, rx_buf->page_offset,
-					   rx_buf->len);
+			skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
+					rx_buf->page, rx_buf->page_offset,
+					rx_buf->len, efx->rx_buffer_truesize);
 			rx_buf->page = NULL;
-			skb->len += rx_buf->len;
-			skb->data_len += rx_buf->len;
+
 			if (skb_shinfo(skb)->nr_frags == n_frags)
 				break;
 
@@ -111,8 +110,6 @@ static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
 		n_frags = 0;
 	}
 
-	skb->truesize += n_frags * efx->rx_buffer_truesize;
-
 	/* Move past the ethernet header */
 	skb->protocol = eth_type_trans(skb, efx->net_dev);