Thanks for the contribution @epitron and welcome around here since it seems to be a first PR. :)

We have a manual section describing how to build the manual to check changes.
I'm getting errors during make, first one is

./installation/installing-pxe.xml: Not feasibly valid:
Line 25:
    22   <para>
    23    This will create a <literal>result</literal> directory containing: 
    24     
    25    <listitem>
    26     <para>
    27       <literal>bzImage</literal> – the Linux kernel 
    28     </para>
     error: element "listitem" not allowed here;

(error is on line 25)

It seems you are not opening the orderedlist ?

Side note: use the provided template when opening a PR and check what you can.
Even for a doc-only contrib, it tells us what you tested. It also refers you to CONTRIBUTING.md :)

Thank you for your contributions.
This has been automatically marked as stale because it has had no activity for 180 days.
If this is still important to you, we ask that you leave a comment below. Your comment can be as simple as "still important to me". This lets people see that at least one person still cares about this. Someone will have to do this at most twice a year if there is no other activity.
Here are suggestions that might help resolve this more quickly:

1. Search for maintainers and people that previously touched the
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Hopefully this has been improved by now. Make a new PR based on all changes in the last years if you're still interested in fixing this. Since there wasn't any response from the original author, it doesn't make sense to me to keep this open any longer.