unified/tests: Remove nanokernel test part from latency_measure

Nanokernel part of the latency_measure test is a subset of the
microkekernel tests. For unified kernel there is no reason to
have nanokernel test - for unified kernel we have to run whole
the set of tests.

Change-Id: Ief176fd9d25e7355e3d3697c3bbc1e953b16655c
Signed-off-by: Dmitriy Korovkin <dmitriy.korovkin@windriver.com>