Comment # 3 on bug 103168 from Chris Wilson

Test removed in

commit 22fdae38cbad3794a315bfd8d9fd833eba4a35dc
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Wed Oct 11 10:51:22 2017 +0100

    igt/prime_mmap_coherency: Only assert correct usage of sync API

    Ignore the unexpected success when the CPU cache is randomly flushed
    that makes !llc appear to work without sync. It happens, the cpu cache
    is a fickle beast that we do not have sole control over. Instead limit
    the test to detect failures when the API is being adhered to.