[syslinux] tftpd-hpa: the tftpdir is ignored if --secure isn't used

[Alkis Georgopoulos]

If I omit --secure from the tftpd-hpa command line, I then need to e.g.
`tftp -c get /var/lib/tftpboot/vmlinuz` instead of plain /vmlinuz, even
though I pass /var/lib/tftpboot as the tftp dir in the tftpd-hpa command 
line.

That essentially means that I'm exporting my whole /, which is clearly
something I don't want to do. I basically want tftpd-hpa to serve files
from /var/lib/tftpboot but allow symlinks to point outside that dir.

tftpd-hpa version: 5.2-1ubuntu1
cmdline: /usr/sbin/in.tftpd --listen --user tftp --address 0.0.0.0:69
          --verbose /var/lib/tftpboot

Kind regards,
Alkis Georgopoulos