dsa: fix device tree binding documentation typo on #address-cells

The device tree binding documentation for dsa explicitely states that a
DSA node should have its #address-cells property set to 2, yet the
example still used 1, fix that typo.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.txt b/Documentation/devicetree/bindings/net/dsa/dsa.txt
index db92f55..49f4f7a 100644
--- a/Documentation/devicetree/bindings/net/dsa/dsa.txt
+++ b/Documentation/devicetree/bindings/net/dsa/dsa.txt
@@ -43,7 +43,7 @@
 
 	dsa@0 {
 		compatible = "marvell,dsa";
-		#address-cells = <1>;
+		#address-cells = <2>;
 		#size-cells = <0>;
 
 		interrupts = <10>;