nlf_get_u16
int nlf_get_u16(void *src, struct nl_pstate *npt, void *target);
{ .off_in = _IN(ifi_type), .off_out = _OUT(ifi_type), .cb = nlf_get_u16 },
{ .off_in = _IN(ndm_state), .off_out = _OUT(ndm_state), .cb = nlf_get_u16 },