i#58 MacOS: os_thread_sleep()
i#58 MacOS: os_thread_sleep()

Use SYS__semwait_signal as impl for SYS_nanosleep, though it aborts on
interruption for now.

SVN-Revision: 2453

sigma-random/dynamorio,code4bones/dynamorio,code4bones/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,sigma-random/dynamorio,code4bones/dynamorio,sigma-random/dynamorio,bl4ckic3/dynamorio,daksunt/dynamorio,bl4ckic3/dynamorio,daksunt/dynamorio,AmesianX/dynamorio,daksunt/dynamorio,AmesianX/dynamorio,daksunt/dynamorio,code4bones/dynamorio,AmesianX/dynamorio,bl4ckic3/dynamorio,sigma-random/dynamorio,bl4ckic3/dynamorio,sigma-random/dynamorio,daksunt/dynamorio,bl4ckic3/dynamorio,code4bones/dynamorio