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

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

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221125144114.476849-1-krzysztof.kozlowski@linaro.org


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>