drm/nouveau: move set_tile_region to nouveau_exec_engine

In the very least VPE (PMPEG and friends) also has this style of tile
region regs, lets make them just work if/when they get added.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_mem.c b/drivers/gpu/drm/nouveau/nouveau_mem.c
index cf1731b..9c7bc3f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_mem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_mem.c
@@ -51,8 +51,7 @@
 	struct drm_nouveau_private *dev_priv = dev->dev_private;
 	struct nouveau_fifo_engine *pfifo = &dev_priv->engine.fifo;
 	struct nouveau_fb_engine *pfb = &dev_priv->engine.fb;
-	struct nouveau_pgraph_engine *pgraph = &dev_priv->engine.graph;
-	int i = tile - dev_priv->tile.reg;
+	int i = tile - dev_priv->tile.reg, j;
 	unsigned long save;
 
 	nouveau_fence_unref(&tile->fence);
@@ -70,7 +69,10 @@
 	nouveau_wait_for_idle(dev);
 
 	pfb->set_tile_region(dev, i);
-	pgraph->set_tile_region(dev, i);
+	for (j = 0; j < NVOBJ_ENGINE_NR; j++) {
+		if (dev_priv->eng[j] && dev_priv->eng[j]->set_tile_region)
+			dev_priv->eng[j]->set_tile_region(dev, i);
+	}
 
 	pfifo->cache_pull(dev, true);
 	pfifo->reassign(dev, true);