Documentation: Update doxygen config files

- Update the config files to 1.8.13
- Unify the coreboot and coreboot_simple configs.  The only difference
now is that coreboot uses the graphviz library to generate call graphs
and other things, while coreboot_simple does not.  This means that the
doxygen_simple target builds in just over a minute, while the doxygen
build target takes roughly an hour.
- Both targets now only document coreboot proper.  While at times it
might be useful to see links to code from src/vendorcode, 3rdparty, or
util, these directories also really clutter up the doxygen output. To
make it easier to see the coreboot code, all of these directories are
excluded.

Change-Id: Iefc667ee2f65859f151f5a97b7b9d182e8ed31f7
Signed-off-by: Martin Roth <gaumless@gmail.com>
Reviewed-on: https://review.coreboot.org/26390
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2 files changed