remove SET_ETHTOOL_OPS

SET_ETHTOOL_OPS was removed in mainline Linux kernel in
7ad24ea4bf (net: get rid of SET_ETHTOOL_OPS).
remove .phys_id from ethops

.phys_id was removed in mainline Linux kernel in
1ab7b6ac27 (ethtool: remove phys_id from ethtool_ops).