i40e: Re enable Main VSI loopback setting in the reset path

There is an order in which this should happen. It turns out that FW will
not let you change the Loopback setting of the VSI with update VSI prior
to the VEB creation.

Change-ID: I7614ddff8b4c37702930c02f16f8c346aaa64bd1
Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Tested-by: Jim Young <jamesx.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>