Replace osl_waitThread by osl::Thread::wait.
Use std::chrono instead of TimeValue.

Change-Id: I71691d014feeeb0c5d0ba29d048bda8e25e6e7dd
Reviewed-on: https://gerrit.libreoffice.org/57130
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>