Remove build dependency with option from ccache

[Git-Jiro]

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• Have you checked that there aren't other open pull requests for the same formula update/change?
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Remove build dependency on asciidoc because of audit change: #13133

Is this the correct way to handle this for ccache?

[DomT4]

Unfortunately as-is this breaks the --HEAD build:

==> make install
asciidoc -a revnumber=unknown -d manpage -b docbook MANUAL.txt
make: asciidoc: No such file or directory
make: *** [MANUAL.xml] Error 1

[ilovezfs]

Sorry, passing on this, as this will need to be addressed at some point in a way that does not break the build but thanks nonetheless.

[Git-Jiro]

OK, no problem. I will make another PR when I have a solution that works with --HEAD as well.