ARM: dts: omap3/am4372: add missing unit name to ocp node

This patch fixes the following DTC warnings for many boards:

"Node /ocp has a reg or ranges property, but no unit name"

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/boot/dts/omap36xx.dtsi b/arch/arm/boot/dts/omap36xx.dtsi
index 8b797915..718fa88 100644
--- a/arch/arm/boot/dts/omap36xx.dtsi
+++ b/arch/arm/boot/dts/omap36xx.dtsi
@@ -30,7 +30,7 @@
 		};
 	};
 
-	ocp {
+	ocp@68000000 {
 		uart4: serial@49042000 {
 			compatible = "ti,omap3-uart";
 			reg = <0x49042000 0x400>;