drm/i915: Fix formatting for gen8_cs_irq_handler

Requested by Chris, and since we're no longer rebasing the -next queue
I can't rectify history.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Nick Hoath <nicholas.hoath@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445415633-21897-1-git-send-email-daniel.vetter@ffwll.ch


Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>