ARM: dts: armada: align LED node names with dtschema

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

  armada-370-seagate-personal-cloud.dtb: gpio-leds: 'red-sata0' does not match any of the regexes: '(^led-[0-9a-f]$|led)', 'pinctrl-[0-9]+'

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>