i40e: Make sure to be in VEB mode if SRIOV is enabled at probe

If SRIOV is enabled we need to be in VEB mode not VEPA mode at probe.
This fixes an NPAR bug when SRIOV is enabled in the BIOS.

Change-ID: Ibf006abafd9a0ca3698ec24848cd771cf345cbbc
Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Tested-by: Jim Young <james.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>