rebase test cases on latest libc-test

[matthew-l-weber]

The https://github.com/Boeing/libc-test/tree/boeing-staging-next-libc-test represented a series of patches which were sent to the MUSL libc-test project mailing list. They are pending merge into the libc-test project.

This work was done in the past and pending issues have been noticed that are noted below.

The work may also be incorporated into a test scenario that will be tagged below. The scenario may have a updated revision of the test cases that could be used to refresh this branch and/or resume the upstreaming work to libc-test project.

[matthew-l-weber]

A couple of comments

• In line 40 of utils.h, the first comment block doesn't align with the code. It looks like a function was removed? I think the comment should be moved above busy_loop_to_consume_cpu_time in src/functional/times.c

• Starting on line 79 of utils.h, the comment block should be moved above the the create_and_join_threadsfunction.

• The test_buffer_overflow function could use a description.

A review was stopped in the second half of the file (around mq_unlink).

[matthew-l-weber]

Buildroot regression testing using this work - https://patchwork.ozlabs.org/project/buildroot/list/?series=520616