hwmon: ntc_thermistor: Fix typo (pullup-uV -> pullup-uv)

This patch fix typo of property name from 'pullup-uV' to 'pullup-uv'.
The ntc_thermistor.c use 'pullup-uv' when parsing dt data.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>

Documentation/devicetree/bindings/arm/samsung/exynos-adc.txt

@@ -49,7 +49,7 @@ adc@12D10000 {
 	/* NTC thermistor is a hwmon device */
 	ncp15wb473@0 {
 		compatible = "ntc,ncp15wb473";
-		pullup-uV = <1800000>;
+		pullup-uv = <1800000>;
 		pullup-ohm = <47000>;
 		pulldown-ohm = <0>;
 		io-channels = <&adc 4>;