[SK_BUFF]: Introduce skb_copy_to_linear_data{_offset}

To clearly state the intent of copying to linear sk_buffs, _offset being a
overly long variant but interesting for the sake of saving some bytes.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
diff --git a/drivers/net/e100.c b/drivers/net/e100.c
index 0cefef5..4d0e0ae 100644
--- a/drivers/net/e100.c
+++ b/drivers/net/e100.c
@@ -1769,7 +1769,7 @@
 
 	/* Align, init, and map the RFD. */
 	skb_reserve(rx->skb, NET_IP_ALIGN);
-	memcpy(rx->skb->data, &nic->blank_rfd, sizeof(struct rfd));
+	skb_copy_to_linear_data(rx->skb, &nic->blank_rfd, sizeof(struct rfd));
 	rx->dma_addr = pci_map_single(nic->pdev, rx->skb->data,
 		RFD_BUF_LEN, PCI_DMA_BIDIRECTIONAL);