timer_test: remove unused precision values and confusing log

Change-Id: I1570b7096c757d63d23e0950feeeb7230f8a5c9f
diff --git a/tests/timer/timer_test.ok b/tests/timer/timer_test.ok
index 7c00000..22b93aa 100644
--- a/tests/timer/timer_test.ok
+++ b/tests/timer/timer_test.ok
@@ -1,2 +1,2 @@
-Running timer test for 5 steps, accepting imprecision of 0.020000 seconds
+Running timer test for 5 steps
 test over: added=31 expired=31 too_soon=0 too_late=0