Change the name of the adapter in the PTP struct to enable easier
correlation between interface and PTP device.

Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: NMatthew Vick <matthew.vick@intel.com>
Acked-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NJeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>