ARM: dts: sun4i: Rename thermal nodes to avoid warnings

The thermal-zone subnodes we defined for the A10 have underscores in them
that will generate DTC warnings. Change those underscores for hyphens.
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun4i-a10.dtsi

@@ -129,7 +129,7 @@ cpu0: cpu@0 {
 	};
 
 	thermal-zones {
-		cpu_thermal {
+		cpu-thermal {
 			/* milliseconds */
 			polling-delay-passive = <250>;
 			polling-delay = <1000>;
@@ -143,14 +143,14 @@ map0 {
 			};
 
 			trips {
-				cpu_alert0: cpu_alert0 {
+				cpu_alert0: cpu-alert0 {
 					/* milliCelsius */
 					temperature = <850000>;
 					hysteresis = <2000>;
 					type = "passive";
 				};
 
-				cpu_crit: cpu_crit {
+				cpu_crit: cpu-crit {
 					/* milliCelsius */
 					temperature = <100000>;
 					hysteresis = <2000>;