I probably should have done this a long time ago, but now kdesrc-build
has a man page (mostly to get rid of the 1 Debian lintian hit I saw for
1.13)

I haven't tied it into CMake yet because I'm tired, but it requires
asciidoc and the short story is:

$ asciidoc -d manpage -b docbook kdesrc-build.1.txt
$ xsltproc --nonet /usr/share/asciidoc/docbook-xsl/manpage.xsl
kdesrc-build.1.xml

Of course finding that damn XSL from CMake will be the problem in the
future but I can figure that out tomorrow if no other kind soul does
that for me.