igbvf: remove bogus phys_id

This device lies about supporting phys_id. Remove it and just
let the upper layer report not supported.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Tested-by:  <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>