Reinstitate send() after syslogd restarts.

In r228193 the test of CONNPRIV have been moved to before the _usleep
and send in vsyslog(). When syslogd restarts, this would prevent the
message being logged after the disconnect/connect dance for
scenario #1.

PR: 194751
Submitted by: Peter Creath <pjcreath+freebsd gmail com>
Reviewed By: glebius
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D1227