Some systems do not have these types available, and they are simply
convenience aliases. Instead use the expanded versions which are more
portable.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=101192
These inclusions were in place for backward compatibility purposes,
when the headers were split so that code using them would not break.
Make it possible for applications to disable them by defining
LIBBSD_CLEAN_INCLUDES so that buildability can be tested and fixed
before they get removed in a subsequent release.