Revert "Doxygen warnings corrected"

This reverts commit ff8036df5c5575503dc30d255dfbe99cc637c510.

multiple build failures with namespace collisions etc

Change-Id: Ie8ac08feff518af3584a26957f07a60d95932c76
Reviewed-on: https://gerrit.libreoffice.org/7855
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>