Use the `crossref:` macro all documentation internal links except for inter-book links.
This will produce the correct link in Single HTML, Splitted HTML and PDF.
Rework the macro to include the PDF special render.
Apply the changes where apply (basically convert the xref shortcut to crossref)
While here briefly document macros
PR: [[https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=266107|266107]]
Should obsolete:
* https://reviews.freebsd.org/D46265
* https://reviews.freebsd.org/D46264
* https://reviews.freebsd.org/D46263
* https://reviews.freebsd.org/D46262
* https://reviews.freebsd.org/D46261
* https://reviews.freebsd.org/D46260
* https://reviews.freebsd.org/D46258
Dear reviewer: as you can imagine I did not check //all// links in the documentation, but check a fairly amount of them :-)
I'm not worried about possible mistakes now that we have a working solution.
If I accidentally broke a link, I can fix it later.