ARM: dts: aspeed: minipack: Fixup I2C tree

ARM: dts: aspeed: minipack: Fixup I2C tree

Create all the i2c switches in device tree and use aliases to assign
child channels with consistent bus numbers.

Besides, "i2c-mux-idle-disconnect" is set for all the i2c switches to
avoid potential conflicts when multiple devices (beind the switches) use
the same device address.

Signed-off-by: Tao Ren <rentao.bupt@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20201110072446.8218-1-rentao.bupt@gmail.com
Signed-off-by: Joel Stanley <joel@jms.id.au>