first set of i915 fixes, all over.
* tag 'drm-intel-next-fixes-2014-10-17' of git://anongit.freedesktop.org/drm-intel:
drm/i915: fix short vs. long hpd detection
drm/i915: Don't trust the DP_DETECT bit for eDP ports on CHV
drm/i915: properly reenable gen8 pipe IRQs
drm/i915: Move DIV_ROUND_CLOSEST_ULL macro to header
drm/i915: intel_backlight scale() math WA