arm64: dts: freescale: Add DEBIX SOM A and SOM A I/O Board support

Add support for the Debix SOM A + SOM A I/O board. The commit enables
only the basic features like:
 - 2x UART
 - 2x Network
 - eMMC/µSD
 - CAN
 - QSPI
 - USB Host / Device

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>