This makes udevd send log entries to kmsg buffer and sysklogd will
pick them up.
Ideally we should use "syslog" here, but at the time udevd starts,
sysklogd has not started yet and /dev/log does not exist. So udevd
cannot open /dev/log and it will still use stderr as a fallback. We
cannot make udevd depending on sysklogd either, because it would cause a
circular dependency...