failure to send a udp packet is not a fatal error

[David Gwynne]

the tftp proxy on the firewall is dying these days. i managed to
track the failure down to an error sending the udp packet on.

rather than err, i think it more appropriate to warn and let the
client retry in this situation.

ok?

Index: tftp-proxy.c
===================================================================
RCS file: /cvs/src/usr.sbin/tftp-proxy/tftp-proxy.c,v
retrieving revision 1.18
diff -u -p -r1.18 tftp-proxy.c
--- tftp-proxy.c        24 Feb 2016 16:34:47 -0000      1.18
+++ tftp-proxy.c        26 Apr 2016 03:41:39 -0000
@@ -869,7 +869,7 @@ unprivproc_pop(int fd, short events, voi
                if (sendto(s, r->buf, r->buflen, 0,
                    (struct sockaddr *)&r->addrs.dst,
                    r->addrs.dst.ss_len) == -1)
-                       lerr(1, "%s: unable to send", __func__);
+                       lwarn("%s: unable to send", __func__);
 
                close(s);