[PATCH v2] tests: posix: use cpu clock for sleep

[DJ Delorie]

Adhemerval Zanella Netto <adhemerval.zanella@linaro.org> writes:
> I don't think a busy-wait would be a problem for this test, we already
> have some similar tests for clock checks and 1s walltime should be ok.
> DJ, do think it should be a block for this fix?

Given the limitations of his platform, I have no further issues with his
patch.

Reviewed-by: DJ Delorie <dj@redhat.com>