i40evf: Use the correct defines to match the VF registers

Use CTLN1 instead of CTLN for the VF relative register space.

Change-ID: Iefba63faf0307af55fec8dbb64f26059f7d91318
Signed-off-by: Anjali Singhai Jain <anjali.singhai@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>