drm/qxl: use to_qxl_bo macro

Instead of using container_of directly use to_qxl_bo macro.
Signed-off-by: Frediano Ziglio <fziglio@redhat.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450178476-26284-9-git-send-email-boris.brezillon@free-electrons.comSigned-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/qxl/qxl_object.c

@@ -32,7 +32,7 @@ static void qxl_ttm_bo_destroy(struct ttm_buffer_object *tbo)
 	struct qxl_bo *bo;
 	struct qxl_device *qdev;
 
-	bo = container_of(tbo, struct qxl_bo, tbo);
+	bo = to_qxl_bo(tbo);
 	qdev = (struct qxl_device *)bo->gem_base.dev->dev_private;
 
 	qxl_surface_evict(qdev, bo, false);

drivers/gpu/drm/qxl/qxl_ttm.c

@@ -201,7 +201,7 @@ static void qxl_evict_flags(struct ttm_buffer_object *bo,
 		placement->num_busy_placement = 1;
 		return;
 	}
-	qbo = container_of(bo, struct qxl_bo, tbo);
+	qbo = to_qxl_bo(bo);
 	qxl_ttm_placement_from_domain(qbo, QXL_GEM_DOMAIN_CPU, false);
 	*placement = qbo->placement;
 }
@@ -365,7 +365,7 @@ static void qxl_bo_move_notify(struct ttm_buffer_object *bo,
 
 	if (!qxl_ttm_bo_is_qxl_bo(bo))
 		return;
-	qbo = container_of(bo, struct qxl_bo, tbo);
+	qbo = to_qxl_bo(bo);
 	qdev = qbo->gem_base.dev->dev_private;
 
 	if (bo->mem.mem_type == TTM_PL_PRIV0 && qbo->surface_id)