dt-bindings: usb: Add support for Microchip usb5744 hub controller

The Microchip usb5744 is a SS/HS USB 3.0 hub controller with 4 ports.
Add description for USB related aspects of the USB5744 hub, it as
well cover the option of connecting the controller as an i2c slave.
When i2c interface is connected hub needs to be initialized first.
Hub itself has fixed i2c address 0x2D but hardcoding address is not good
idea because address can be shifted by i2c address translator in the
middle.

Signed-off-by: Piyush Mehta <piyush.mehta@amd.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/067fb163bfe3162c596a6c69c96c43ac78288628.1683895176.git.michal.simek@amd.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>