arm64: dts: mediatek: align LED node names with dtschema

The node names should be generic and DT schema expects certain pattern:

  mediatek/mt8183-kukui-jacuzzi-fennel-sku1.dtb: pwmleds: 'keyboard-backlight' does not match any of the regexes: '^led(-[0-9a-f]+)?$', 'pinctrl-[0-9]+'
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221125144138.477198-1-krzysztof.kozlowski@linaro.orgSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8183-kukui-jacuzzi-fennel-sku1.dts

@@ -13,7 +13,7 @@ / {
 
 	pwmleds {
 		compatible = "pwm-leds";
-		keyboard_backlight: keyboard-backlight {
+		keyboard_backlight: led-0 {
 			label = "cros_ec::kbd_backlight";
 			pwms = <&cros_ec_pwm 0>;
 			max-brightness = <1023>;