[SK_BUFF]: Introduce skb_copy_from_linear_data{_offset}

To clearly state the intent of copying from 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@redhat.com>
diff --git a/drivers/message/fusion/mptlan.c b/drivers/message/fusion/mptlan.c
index 21fe1b6..7dd34bd 100644
--- a/drivers/message/fusion/mptlan.c
+++ b/drivers/message/fusion/mptlan.c
@@ -932,7 +932,7 @@
 		pci_dma_sync_single_for_cpu(mpt_dev->pcidev, priv->RcvCtl[ctx].dma,
 					    priv->RcvCtl[ctx].len, PCI_DMA_FROMDEVICE);
 
-		memcpy(skb_put(skb, len), old_skb->data, len);
+		skb_copy_from_linear_data(old_skb, skb_put(skb, len), len);
 
 		pci_dma_sync_single_for_device(mpt_dev->pcidev, priv->RcvCtl[ctx].dma,
 					       priv->RcvCtl[ctx].len, PCI_DMA_FROMDEVICE);
@@ -1093,7 +1093,7 @@
 						    priv->RcvCtl[ctx].dma,
 						    priv->RcvCtl[ctx].len,
 						    PCI_DMA_FROMDEVICE);
-			memcpy(skb_put(skb, l), old_skb->data, l);
+			skb_copy_from_linear_data(old_skb, skb_put(skb, l), l);
 
 			pci_dma_sync_single_for_device(mpt_dev->pcidev,
 						       priv->RcvCtl[ctx].dma,
@@ -1122,7 +1122,7 @@
 					    priv->RcvCtl[ctx].len,
 					    PCI_DMA_FROMDEVICE);
 
-		memcpy(skb_put(skb, len), old_skb->data, len);
+		skb_copy_from_linear_data(old_skb, skb_put(skb, len), len);
 
 		pci_dma_sync_single_for_device(mpt_dev->pcidev,
 					       priv->RcvCtl[ctx].dma,