ARM: dts: sun5i: Remove SoC node unit-name to avoid warnings

Our main node for all the in-SoC controllers used to have a unit name. The
unit-name, in addition to being actually false, would not match any reg
property, which generates a warning.

Remove it in order to remove those warnings.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>

arch/arm/boot/dts/sun5i-a10s.dtsi

@@ -74,7 +74,7 @@ display-engine {
 		allwinner,pipelines = <&fe0>;
 	};
 
-	soc@1c00000 {
+	soc {
 		hdmi: hdmi@1c16000 {
 			compatible = "allwinner,sun5i-a10s-hdmi";
 			reg = <0x01c16000 0x1000>;

arch/arm/boot/dts/sun5i-a13.dtsi

@@ -86,7 +86,7 @@ display-engine {
 		allwinner,pipelines = <&fe0>;
 	};
 
-	soc@1c00000 {
+	soc {
 		pwm: pwm@1c20e00 {
 			compatible = "allwinner,sun5i-a13-pwm";
 			reg = <0x01c20e00 0xc>;

arch/arm/boot/dts/sun5i-gr8.dtsi

@@ -54,7 +54,7 @@ display-engine {
 		allwinner,pipelines = <&fe0>;
 	};
 
-	soc@1c00000 {
+	soc {
 		pwm: pwm@1c20e00 {
 			compatible = "allwinner,sun5i-a10s-pwm";
 			reg = <0x01c20e00 0xc>;

arch/arm/boot/dts/sun5i.dtsi

@@ -123,7 +123,7 @@ cma_pool: cma@4a000000 {
 		};
 	};
 
-	soc@1c00000 {
+	soc {
 		compatible = "simple-bus";
 		#address-cells = <1>;
 		#size-cells = <1>;