drm/nouveau: remove (most) hardcoded object handle usage

The PFIFO<->EVO sync buffers will be fixed up later when inter-channel
sync in general is improved.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index d222875..23146ce 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -765,9 +765,9 @@
 		BEGIN_NV04(chan, NvSubCopy, 0x0000, 1);
 		OUT_RING  (chan, handle);
 		BEGIN_NV04(chan, NvSubCopy, 0x0180, 3);
-		OUT_RING  (chan, NvNotify0);
-		OUT_RING  (chan, NvDmaFB);
-		OUT_RING  (chan, NvDmaFB);
+		OUT_RING  (chan, chan->drm->ntfy.handle);
+		OUT_RING  (chan, chan->vram.handle);
+		OUT_RING  (chan, chan->vram.handle);
 	}
 
 	return ret;
@@ -854,7 +854,7 @@
 		BEGIN_NV04(chan, NvSubCopy, 0x0000, 1);
 		OUT_RING  (chan, handle);
 		BEGIN_NV04(chan, NvSubCopy, 0x0180, 1);
-		OUT_RING  (chan, NvNotify0);
+		OUT_RING  (chan, chan->drm->ntfy.handle);
 	}
 
 	return ret;
@@ -866,7 +866,7 @@
 {
 	if (mem->mem_type == TTM_PL_TT)
 		return NvDmaTT;
-	return NvDmaFB;
+	return chan->vram.handle;
 }
 
 static int