Mauro Carvalho Chehab [off-list ref] writes:

When one does:
	make SPHINXDIRS="foo" htmldocs

All patterns would be relative to Documentation/foo, which
causes the include/exclude patterns like:

	include_patterns = [
		...
		f'foo/*.{ext}',
	]

to break. This is not what it is expected. Address it by
adding a logic to dynamically adjust the pattern when
SPHINXDIRS is used.

That allows adding parsers for other file types.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Reviewed-by: Donald Hunter <donald.hunter@gmail.com>