i40evf: allow enabling of debug prints via ethtool

Copy setting from ethtool to the HW specific struct to actually
enable prints.  Change print from i40e to i40evf to differentiate
drivers in bare metal scenarios.

Also update the copyright year.

Change-ID: I06fee26247299a08f2e1c70fc811a9ea0931c4dd
Signed-off-by: Ashish Shah <ashish.n.shah@intel.com>
Tested-by: Jim Young <james.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>