On 82574, 82583, 82579, I217 and I218 add support for hardware time
stamping of all or no Rx packets and Tx packets which have the
SKBTX_HW_TSTAMP flag set.  Update the .get_ts_info ethtool operation to
report the supported time stamping modes, and enable and disable hardware
time stamping with the SIOCSHWTSTAMP ioctl.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>