Simple change in UDP message sending to shutup Valgrind

sk_sendmsg(sock *s)

{

  struct iovec iov = {s->tbuf, s->tpos - s->tbuf};

  byte cmsg_buf[CMSG_TX_SPACE];

  sockaddr dst;

  static _Thread_local byte cmsg_buf[CMSG_TX_SPACE] = {};

  static _Thread_local sockaddr dst = {};

  int flags = 0;

  sockaddr_fill(&dst, s->af, s->daddr, s->iface, s->dport);