apbuart: Use of_find_node_by_path to find root node.

Signed-off-by: NKristoffer Glembo <kristoffer@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/serial/apbuart.c

@@ -609,7 +609,7 @@ static void grlib_apbuart_configure(void)
 		return;
 
 	/* Get bus frequency */
-	rp = of_find_node_by_name(NULL, "/");
+	rp = of_find_node_by_path("/");
 	rp = of_get_next_child(rp, NULL);
 	prop = of_get_property(rp, "clock-frequency", NULL);
 	freq_khz = *prop;