ARM: dts: update watchdog node name in exynos5440

Made it as per DT node naming convention <name@reg_addr>.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/boot/dts/exynos5440.dtsi

@@ -176,7 +176,7 @@ i2c@100000 {
 		clock-names = "i2c";
 	};
 
-	watchdog {
+	watchdog@110000 {
 		compatible = "samsung,s3c2410-wdt";
 		reg = <0x110000 0x1000>;
 		interrupts = <0 1 0>;