igb: Add 1588 support to I210/I211.

Previously I210/I211 followed the same code flow as 82580/I350 for 1588.
However, since the register sets have changed, we must update the
implementation to accommodate the register changes.

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