e1000e: Use skb_copy_to_linear_data_offset introduced in 2.6.22

The e1000e driver was based on a version of e1000 prior to acme's
introduction of skb_copy_to_linear_data_offset, and was submitted
after acme went through and coverted all the drivers to use it.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>