board: toradex: add apalis imx8qm 4gb wb it v1.0b module support

This commit adds initial support for the Toradex Apalis iMX8QM 4GB WB IT
V1.0B module. Unlike the V1.0A early access samples exclusively booting
from SD card, they are now strapped to boot from eFuses which are
factory fused to properly boot from their on-module eMMC. U-Boot
supports either booting from the on-module eMMC or may be used for
recovery purpose using the universal update utility (uuu) aka mfgtools
3.0.

Functionality wise the following is known to be working:
- eMMC, 8-bit and 4-bit MMC/SD card slots
- Gigabit Ethernet
- GPIOs
- I2C

Unfortunately, there is no USB functionality for the i.MX 8QM as of yet.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reviewed-by: Max Krummenacher <max.krummenacher@toradex.com>