i40e: use generic vsi_open to unquiesce vsi

Use the new i40e_vsi_open() for waking VSIs back up in order to
be sure all the standard actions happen.

Change-ID: Ic3479410dd3079733f4951dcea69f101e69e77df
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Catherine Sullivan <catherine.sullivan@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>