ARM: dts: at91: sama5d4: add labels to soc dtsi for derivative boards

This adds labels to commonly used device-tree nodes so that derivative
boards can avoid ahb/apb hierarchy.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

arch/arm/boot/dts/sama5d4.dtsi

@@ -1323,13 +1323,13 @@ pmecc: ecc-engine@ffffc070 {
 				};
 			};
 
-			rstc@fc068600 {
+			reset_controller: rstc@fc068600 {
 				compatible = "atmel,sama5d3-rstc", "atmel,at91sam9g45-rstc";
 				reg = <0xfc068600 0x10>;
 				clocks = <&clk32k>;
 			};
 
-			shdwc@fc068610 {
+			shutdown_controller: shdwc@fc068610 {
 				compatible = "atmel,at91sam9x5-shdwc";
 				reg = <0xfc068610 0x10>;
 				clocks = <&clk32k>;
@@ -1342,7 +1342,7 @@ pit: timer@fc068630 {
 				clocks = <&h32ck>;
 			};
 
-			watchdog@fc068640 {
+			watchdog: watchdog@fc068640 {
 				compatible = "atmel,sama5d4-wdt";
 				reg = <0xfc068640 0x10>;
 				interrupts = <4 IRQ_TYPE_LEVEL_HIGH 7>;
@@ -1376,7 +1376,7 @@ dbgu: serial@fc069000 {
 			};
 
 
-			pinctrl@fc06a000 {
+			pinctrl: pinctrl@fc06a000 {
 				#address-cells = <1>;
 				#size-cells = <1>;
 				compatible = "atmel,sama5d3-pinctrl", "atmel,at91sam9x5-pinctrl", "simple-bus";