This patch adds support for setting/getting FEC configuration
using ethtool options:
       set/show-priv-flags rs-fec/base-r-fec
       set/show-fec off/rs/baser/auto for kernels version >= 4.14
Signed-off-by: NDamian Dybek <damian.dybek@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>