ETHTOOL_A_LINKSTATE_HEADER
phydev = ethnl_req_get_phydev(req_base, tb, ETHTOOL_A_LINKSTATE_HEADER,
.hdr_attr = ETHTOOL_A_LINKSTATE_HEADER,
[ETHTOOL_A_LINKSTATE_HEADER] =
extern const struct nla_policy ethnl_linkstate_get_policy[ETHTOOL_A_LINKSTATE_HEADER + 1];