With some divider values we end up with the wrong result.  So remove the
intermediates (like Ville suggested in the first place) to get the right
answer.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>