refactor: Radxa S0 overlay are replaced with reference syntax

Author: CodeChenL

arch/arm64/boot/dts/rockchip/overlays/radxa-s0-ext-antenna.dts

@@ -11,43 +11,30 @@
 		exclusive = "GPIO0_A6", "GPIO0_A5";
 		description = "Enable External Antenna.";
 	};
+};
 
-	fragment@0 {
-		target-path = "/";
-
-		__overlay__ {
-			ext_antenna: ext-antenna {
-				status = "okay";
-				compatible = "regulator-fixed";
-				enable-active-low;
-				gpio = <&gpio0 RK_PA6 GPIO_ACTIVE_LOW>;
-				regulator-always-on;
-				regulator-boot-on;
-				pinctrl-0 = <&ant_2>;
-				pinctrl-names = "default";
-				regulator-name = "ext_antenna";
-			};
-		};
-	};
-
-	fragment@1 {
-		target = <&board_antenna>;
-
-		__overlay__ {
-			status = "disabled";
-		};
+&{/} {
+	ext_antenna: ext-antenna {
+		status = "okay";
+		compatible = "regulator-fixed";
+		enable-active-low;
+		gpio = <&gpio0 RK_PA6 GPIO_ACTIVE_LOW>;
+		regulator-always-on;
+		regulator-boot-on;
+		pinctrl-0 = <&ant_2>;
+		pinctrl-names = "default";
+		regulator-name = "ext_antenna";
 	};
+};
 
-	fragment@2 {
-		target = <&pinctrl>;
+&board_antenna {
+	status = "disabled";
+};
 
-		__overlay__ {
-			antenna {
-				ant_2: ant-2 {
-					rockchip,pins = <0 RK_PA6 RK_FUNC_GPIO &pcfg_pull_down>;
-				};
-			};
+&pinctrl {
+	antenna {
+		ant_2: ant-2 {
+			rockchip,pins = <0 RK_PA6 RK_FUNC_GPIO &pcfg_pull_down>;
 		};
 	};
 };
-