This patch adds document for the machine board with mt6358, rt1015 and rt5682. Signed-off-by: Jiaxin Yu <jiaxin.yu@mediatek.com> Link: https://lore.kernel.org/r/1604390378-23993-10-git-send-email-jiaxin.yu@mediatek.com Signed-off-by: Mark Brown <broonie@kernel.org>