ARM: dts: microchip: at91: align LED node name with bindings

Bindings expect the LED node names to follow certain pattern, see
dtbs_check warnings:

at91sam9g15ek.dtb: leds: 'pb18', 'pd21' do not match any of the regexes: '(^led-[0-9a-f]$|led)', 'pinctrl-[0-9]+'

Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Reviewed-by: Alexander Dahl <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Claudiu Beznea <[e-mail]>

arch/arm/boot/dts/microchip/at91sam9g20ek_2mmc.dts

···
 	leds {
 		compatible = "gpio-leds";
 
-		ds1 {
+		led-ds1 {
 			label = "ds1";
 			gpios = <&pioB 9 GPIO_ACTIVE_HIGH>;
 			linux,default-trigger = "heartbeat";
 		};
 
-		ds5 {
+		led-ds5 {
 			label = "ds5";
 			gpios = <&pioB 8 GPIO_ACTIVE_LOW>;
 		};

arch/arm/boot/dts/microchip/at91sam9g25-gardena-smart-gateway.dts

···
 	leds {
 		compatible = "gpio-leds";
 
-		power_blue {
+		led-power-blue {
 			label = "smartgw:power:blue";
 			gpios = <&pioC 21 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		power_green {
+		led-power-green {
 			label = "smartgw:power:green";
 			gpios = <&pioC 20 GPIO_ACTIVE_HIGH>;
 			default-state = "on";
 		};
 
-		power_red {
+		led-power-red {
 			label = "smartgw:power:red";
 			gpios = <&pioC 19 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		radio_blue {
+		led-radio-blue {
 			label = "smartgw:radio:blue";
 			gpios = <&pioC 18 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		radio_green {
+		led-radio-green {
 			label = "smartgw:radio:green";
 			gpios = <&pioC 17 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		radio_red {
+		led-radio-red {
 			label = "smartgw:radio:red";
 			gpios = <&pioC 16 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		internet_blue {
+		led-internet-blue {
 			label = "smartgw:internet:blue";
 			gpios = <&pioC 15 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		internet_green {
+		led-internet-green {
 			label = "smartgw:internet:green";
 			gpios = <&pioC 14 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		internet_red {
+		led-internet-red {
 			label = "smartgw:internet:red";
 			gpios = <&pioC 13 GPIO_ACTIVE_HIGH>;
 			default-state = "off";
 		};
 
-		heartbeat {
+		led-heartbeat {
 			label = "smartgw:heartbeat";
 			gpios = <&pioB 8 GPIO_ACTIVE_HIGH>;
 			linux,default-trigger = "heartbeat";
 		};
 
-		pb18 {
+		led-pb18 {
 			status = "disabled";
 		};
 
-		pd21 {
+		led-pd21 {
 			status = "disabled";
 		};
 	};

arch/arm/boot/dts/microchip/at91sam9n12ek.dts

···
 	leds {
 		compatible = "gpio-leds";
 
-		d8 {
+		led-d8 {
 			label = "d8";
 			gpios = <&pioB 4 GPIO_ACTIVE_LOW>;
 			linux,default-trigger = "mmc0";
 		};
 
-		d9 {
+		led-d9 {
 			label = "d9";
 			gpios = <&pioB 5 GPIO_ACTIVE_LOW>;
 			linux,default-trigger = "nand-disk";
 		};
 
-		d10 {
+		led-d10 {
 			label = "d10";
 			gpios = <&pioB 6 GPIO_ACTIVE_HIGH>;
 			linux,default-trigger = "heartbeat";

arch/arm/boot/dts/microchip/at91sam9x5cm.dtsi

···
 	leds {
 		compatible = "gpio-leds";
 
-		pb18 {
+		led-pb18 {
 			label = "pb18";
 			gpios = <&pioB 18 GPIO_ACTIVE_LOW>;
 			linux,default-trigger = "heartbeat";
 		};
 
-		pd21 {
+		led-pd21 {
 			label = "pd21";
 			gpios = <&pioD 21 GPIO_ACTIVE_HIGH>;
 		};