ixgbe: don't check minimum link when direct assigned to virtual machine

This patch prevents the display of the minimum link qualification check
if we might be in a virtual machine. This check is incorrect and
misleading in this case, since we actually don't really know what the
available bandwidth is. To do so, we simply check whether each function
on the bus matches our device id. If it doesn't the most likely scenario
is that we're directly assigned to a virtual machine.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>