drm/i915: Add dev to ppgtt

Some subsequent commits will need to know what generation we're running
on to do different pte encoding for the ppgtt. Since it's not much
hassle or overhead to store it in the ppgtt structure, do that.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index f5120d0..a2c5e89 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -345,6 +345,7 @@
 #define I915_PPGTT_PD_ENTRIES 512
 #define I915_PPGTT_PT_ENTRIES 1024
 struct i915_hw_ppgtt {
+	struct drm_device *dev;
 	unsigned num_pd_entries;
 	struct page **pt_pages;
 	uint32_t pd_offset;