ARM: dts: Change iio_hwmon nodes to use hypen in node names

Change iio_hwmon nodes to use hypen in node names instead of
underscore.

Signed-off-by: Sanchayan Maity <[e-mail]>
Signed-off-by: Guenter Roeck <[e-mail]>

Documentation/devicetree/bindings/iio/iio-bindings.txt

···
 
 	...
 
-	iio_hwmon {
+	iio-hwmon {
 		compatible = "iio-hwmon";
 		io-channels = <&adc 0>, <&adc 1>, <&adc 2>,
 			<&adc 3>, <&adc 4>, <&adc 5>,

arch/arm/boot/dts/imx23.dtsi

···
 		};
 	};
 
-	iio_hwmon {
+	iio-hwmon {
 		compatible = "iio-hwmon";
 		io-channels = <&lradc 8>;
 	};

arch/arm/boot/dts/imx28.dtsi

···
 		};
 	};
 
-	iio_hwmon {
+	iio-hwmon {
 		compatible = "iio-hwmon";
 		io-channels = <&lradc 8>;
 	};