i40e: Change the ethtool NVM read method to use AQ

Earlier we were reading Shadow RAM (copy of the NVM) which can differ
from the actual NVM. Use AQ instead to read the actual NVM.

Change-Id: Ia0f2773b722db77d093f738c068af872be69bbd4
Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>