The principal purpose of this change is to remove librtkaio support.
The Fedora system wide change request is here:
https://fedoraproject.org/wiki/Changes/GLIBC223_librtkaio_removal
- Build require gcc-c++ for the C++ tests.
- Support --without testsuite option to disable testing after build.
- Support --without benchtests option to disable microbenchmarks.
- Update --with bootstrap to disable benchtests, valgrind, documentation,
selinux, and nss-crypt during bootstrap.
- Support --without werror to disable building with -Werror.
- Support --without docs to disable build requirement on texinfo.
- Support --without valgrind to disable testing with valgrind.
- Remove c_stubs add-on and enable fuller support for static binaries.
- Remove librtkaio support (#1227855).
