[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/net/bnx2.c b/drivers/net/bnx2.c
index 7e7b5f3..f98a220 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -1884,10 +1884,8 @@
 				goto reuse_rx;
 
 			/* aligned copy */
-			memcpy(new_skb->data,
-				skb->data + bp->rx_offset - 2,
-				len + 2);
-
+			skb_copy_from_linear_data_offset(skb, bp->rx_offset - 2,
+				      new_skb->data, len + 2);
 			skb_reserve(new_skb, 2);
 			skb_put(new_skb, len);