4870. [test] Update included ATF library to atf-0.21 preserving the ATF tool. [RT #46967] (cherry picked from commit 23d77c8747bee67dd01c4cf5096760611fd65f01)
3043. [test] Merged in the NetBSD ATF test framework (currently version 0.12) for development of future unit tests. Use configure --with-atf to build ATF internally or configure --with-atf=prefix to use an external copy. [RT #23209]