dm: core: Update device_bind_driver_to_node() to use ofnode

Adjust this function to us an ofnode instead of an offset, so it can be
used with livetree. This involves updating all callers.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/cpu/cpu-uclass.c b/drivers/cpu/cpu-uclass.c
index c57ac16..73e4853 100644
--- a/drivers/cpu/cpu-uclass.c
+++ b/drivers/cpu/cpu-uclass.c
@@ -63,11 +63,11 @@
 static int uclass_cpu_init(struct uclass *uc)
 {
 	struct udevice *dev;
-	int node;
+	ofnode node;
 	int ret;
 
-	node = fdt_path_offset(gd->fdt_blob, "/cpus");
-	if (node < 0)
+	node = ofnode_path("/cpus");
+	if (!ofnode_valid(node))
 		return 0;
 
 	ret = device_bind_driver_to_node(dm_root(), "cpu_bus", "cpus", node,