drm/i915: Eliminate superfluous i915_ggtt_view_normal

Since commit 058d88c4330f ("drm/i915: Track pinned VMA"), there is only
one user of i915_ggtt_view_normal rodate. Just treat NULL as no special
view in pin_to_display() like everywhere else.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170114002827.31315-7-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index 4473a61..0608fad 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -811,8 +811,7 @@ static int intel_overlay_do_put_image(struct intel_overlay *overlay,
 	if (ret != 0)
 		return ret;
 
-	vma = i915_gem_object_pin_to_display_plane(new_bo, 0,
-						   &i915_ggtt_view_normal);
+	vma = i915_gem_object_pin_to_display_plane(new_bo, 0, NULL);
 	if (IS_ERR(vma))
 		return PTR_ERR(vma);