syslog needs a valid socket path for _PATH_LOG

/dev/kmsg is a character device already used for different purposes.
Most distribution use /dev/log for _PATH_LOG but this path is already used
by logcat.
I suggest using /dev/syslog.
This change was tested with busybox's syslogd.

Change-Id: I75b428123c7a0b3ca4bea656ce06860f6f727dde