dt-bindings: arm: aspeed: document Delta AHE-50DC BMC

Document Delta AHE-50DC BMC board compatible.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221108001551.18175-2-zev@bewilderbeest.net


Signed-off-by: Joel Stanley <joel@jms.id.au>