Clean up the INPUT paths for doxygen scanning:
- directory scans include sub-directories so no need
to include them explicitly
- remove excluded (legacy) includes that no longer exist
Sync directory changes in the CMakeLists.txt (as noted in the comments)
Add content to the home page of the doxygen-generated HTML, and add a
Zephyr branding theme.
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Fixes: #6773
David B. Kinder