drm/i915: Wrap drm_gem_object_lookup in i915_gem_object_lookup

For symmetry with a forthcoming i915_gem_object_get() and
i915_gem_object_put().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1469005202-9659-4-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1469017917-15134-3-git-send-email-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index 8030199..46e80f3 100644
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -166,8 +166,8 @@
 	struct drm_i915_gem_object *obj;
 	int ret = 0;
 
-	obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
-	if (&obj->base == NULL)
+	obj = i915_gem_object_lookup(file, args->handle);
+	if (!obj)
 		return -ENOENT;
 
 	if (!i915_tiling_ok(dev,
@@ -297,8 +297,8 @@
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	struct drm_i915_gem_object *obj;
 
-	obj = to_intel_bo(drm_gem_object_lookup(file, args->handle));
-	if (&obj->base == NULL)
+	obj = i915_gem_object_lookup(file, args->handle);
+	if (!obj)
 		return -ENOENT;
 
 	mutex_lock(&dev->struct_mutex);