ARM: dts: Add omap4-hwspinlock support in dm816x

Add dm816x DT entries for omap4-hwspinlock support as hwmod spinbox.

Cc: Brian Hutchinson <b.hutchman@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dm816x.dtsi

@@ -225,6 +225,13 @@ mbox_dsp: mbox_dsp {
 			};
 		};
 
+		spinbox: spinbox@480ca000 {
+			compatible = "ti,omap4-hwspinlock";
+			reg = <0x480ca000 0x2000>;
+			ti,hwmods = "spinbox";
+			#hwlock-cells = <1>;
+		};
+
 		mdio: mdio@4a100800 {
 			compatible = "ti,davinci_mdio";
 			#address-cells = <1>;