rockchip: dts: rk3399-puma: add a 'tsd, usb-port-power' stringlist for USB1

rockchip: dts: rk3399-puma: add a 'tsd, usb-port-power' stringlist for USB1

USB1 is connected to the on-module USB 3.0 hub and power to the hub
(actually it's a reset signal, modeled as a fixed regulator, that will
be released) should be enabled only during the first probing of the
device to avoid the hub from entering its low-power mode (where it
tries to attach on a fixed interval, but we always miss the timeslot
when U-Boot has the controller listening).

This adds a 'tsd,usb-port-power' stringlist to enable the
infrastructure in the board-specific usb_hub_reset_devices to find and
control the fixed regulator associated with control of the USB hub.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>