i40e: main driver core

This is the driver for the Intel(R) Ethernet Controller XL710 Family.

This driver is targeted at basic ethernet functionality only, and will be
improved upon further as time goes on.

This patch contains the driver entry points but does not include transmit
and receive (see the next patch in the series) routines.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
CC: PJ Waskiewicz <peter.p.waskiewicz.jr@intel.com>
CC: e1000-devel@lists.sourceforge.net
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>