AW: use of posix function clock_gettime

[<mario_molitor@web.de>]

> First of all, all in-kernel APIs have been deprecated and removed in favor of RTDM driver APIs. However, RTDM does not expose this clock directly. You can only do rtdm_clock_read (realtime) or rtdm_clock_read_monotonic().

This was also my recognising after reading the code and the information was not really new. Anyway in meantime I have found a workaround/ solution for our problem.

>We could add a host_realtime API to RTDM if there is a good use case. And that would include a reason why the timestamp adjustment (monotonic -> host-realtime) cannot be done in the userspace application that consumes the driver data.

>From my point of view make this always sense if a measurement value needs an accurate Timestamp by the creating. The other applications which could need this are fieldbus application. 
Our measurement system gets her measurement value in the Kernel-Space in a Xenomia-IRQ and in this case was the old Functionality very smart. 
A new Functionality RTDM_ host_realtime would be close this gap and would by also make the RTDM Clock-service completely.

Mario

HBK