more clock_* support

[Ulrich Drepper]

Hi,

I've checked in some changes to implement more clock_* functionality.
For x86 we have now a clock which is using the TSC.  Both Linux and
Hurd should have the functionality (although it cannot quite yet work
on Hurd since I don't know how to get the processor frequency; Roland,
Mark, your call).

The new function from one of the latest POSIX drafts to get the ID of
such a counter is also included.

But: the code is really untested.  It's too late now, will do this
tomorrow.

One thing you'll notice is that the clock_* and timer_* functions are
moved into librt.  This is not only where other platforms have them,
we have to have them there because of the upcoming timer_*
implementation which will, lacking kernel support, use threads.  Since
the functions were not in glibc 2.1 there is not compatiblity issue.

-- 
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Ulrich Drepper  \    ,-------------------'   \  Sunnyvale, CA 94089 USA
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