Documentation: Add several fixes
* Add support for Sphinx 3.0+
* Add backward support for Sphinx 1.8 and older
* Make sphinxcontrib ditaa an optional extension
* Allow SPHINXOPTS to be set from command line
* Add sphinx and sphinx-lint to top level Makefile
Change-Id: If10aef51dc426445cb742aad13b19ee7fe169c51
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41492
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/Documentation/Makefile.sphinx b/Documentation/Makefile.sphinx
index caa8190..6930130 100644
--- a/Documentation/Makefile.sphinx
+++ b/Documentation/Makefile.sphinx
@@ -2,7 +2,7 @@
#
# You can set these variables from the command line.
-SPHINXOPTS =
+SPHINXOPTS ?=
SPHINXBUILD = sphinx-build
SPHINXAUTOBUILD = sphinx-autobuild
PAPER =