Netlink: Fixes uninitialized variable

  struct {

    struct nlmsghdr nh;

    struct rtgenmsg g;

  } req;

  req.nh.nlmsg_type = cmd;

  req.nh.nlmsg_len = sizeof(req);

  req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;

  req.g.rtgen_family = af;

  } req = {

    .nh.nlmsg_type = cmd,

    .nh.nlmsg_len = sizeof(req),

    .nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP,

    .g.rtgen_family = af

  };

  nl_send(&nl_scan, &req.nh);

}