updates to fai-cd

[Thomas Lange]

>>>>> On Fri, 23 Jul 2021 11:12:18 +0200, Sinh Lam <sinh.lam at inviarobotics.com> said:

    > Some of these options are not valid in the version of xorriso that’s available in 16.04 (or 20.04 for that matter).  I’ve even tried looking for this version on a Debian server and they
    > aren’t there.  

Can you please provide some error output. Which options are not
supported? On when Debian version did you also had these errors? Which
xorriso version on Debian?

-- 
viele Grüße Thomas