Add MT7622 i2c binding to binding file. Compare to MT8173 i2c
controller, MT7622 limits message numbers to 255, and does not
support 4GB DMA mode.
Signed-off-by: Jun Gao <jun.gao@mediatek.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>