igb: Don't add PHY address to PCDL address

There is no reason to add the PHY address into the PCDL register address.

Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>