Add optional revision-id standard LPDDR2 properties which will help to identify memory chip. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Reviewed-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20211006224659.21434-4-digetx@gmail.com Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>