The max frequency reporting is not correct. But there is already an existing
valleyview_rps_max_freq and valleyview_rps_min_freq to get the
frequency. Use that for i915_cur_delayinfo.
Signed-off-by: Chon Ming Lee <chon.ming.lee@intel.com> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>