This change adds support for the Linux PTP Hardware clock and timestamping
functionality provided by the hardware.  There are actually two cases that
this timestamping is meant to support.

The first case would be an ordinary clock scenario.  In this configuration
the host interface does not have access to BAR 4.  However all of the host
interfaces should be locked into the same boundary clock region and as such
they are all on the same clock anyway.  With this being the case they can
synchronize among themselves and only need to adjust the offset since they
are all on the same clock with the same frequency.

The second case is a boundary clock scenario.  This is a special case and
would require both BAR 4 access, and a means of presenting a netdev per
boundary region.  The current plan is to use DSA at some point in the
future to provide these interfaces, but the DSA portion is still under
development.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Acked-by: NRichard Cochran <richardcochran@gmail.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>