LU-16666 doc: remove unmaintained doxyfiles

LU-16666 doc: remove unmaintained doxyfiles

These Doxygen related files had old urls, some using http rather
than https. Some code scanning tools will flag this. Rather than
update these, remove all of the old doxyfiles. They are very out
of date, Doxygen throws many errors when you try to use them, and
they do not seem to generate usable documentation.

Test-Parameters: trivial
Signed-off-by: Timothy Day <timday@amazon.com>
Change-Id: I5a24d4754582ecee558c4e87385b8835d2675adc
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/50415
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Aurelien Degremont <adegremont@nvidia.com>
Reviewed-by: Patrick Farrell <pfarrell@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>