MFC r239347, 240295, 240296 and 253325:

MFC r239347, 240295, 240296 and 253325:

    r239347 | davidxu | 2012-08-17 10:26:31 +0800 (Fri, 17 Aug 2012) | 7 lines

    Implement syscall clock_getcpuclockid2, so we can get a clock id
    for process, thread or others we want to support.
    Use the syscall to implement POSIX API clock_getcpuclock and
    pthread_getcpuclockid.

    PR:	168417

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    r240295 | davidxu | 2012-09-10 13:00:29 +0800 (Mon, 10 Sep 2012) | 2 lines

    Add missing prototype for clock_getcpuclockid.

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    r240296 | davidxu | 2012-09-10 13:09:39 +0800 (Mon, 10 Sep 2012) | 2 lines

    Process CPU-Time Clocks option is supported, define _POSIX_CPUTIME.

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    r253325 | kib | 2013-07-14 03:32:50 +0800 (Sun, 14 Jul 2013) | 6 lines

    Allow to call clock_gettime() on the clock id for zombie process.

    Reported by:	Petr Salinger <Petr.Salinger@seznam.cz>
    PR:	threads/180496
    Sponsored by:	The FreeBSD Foundation

git-svn-id: svn://svn.freebsd.org/base/stable/9@254398 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f