arm64: dts: freescale: add initial support for colibri imx8x

This patch adds the device tree to support Toradex Colibri iMX8X a
computer on module which can be used on different carrier boards.

The module consists of an NXP i.MX 8X family SoC (either i.MX 8DualX or
8QuadXPlus), a PF8100 PMIC, a FastEthernet PHY, 1 or 2 GB of LPDDR4
RAM, some level shifters, a Micron eMMC, a USB hub, an AD7879 resistive
touch controller, an SGTL5000 audio codec and on-module CSI as well as
DSI-LVDS FFC receptacles plus an optional Bluetooth/Wi-Fi module.

Anything that is not self-contained on the module is disabled by
default.

The device tree for the Colibri Evaluation Board includes the module's
device tree and enables the supported peripherals of the carrier board
(the Colibri Evaluation Board supports almost all of them).

So far there is no display or USB functionality supported at all but
basic console UART, eMMC and Ethernet functionality work fine.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>