arm: imx: Add support for Google's Coral Dev Board

Add initial support for Google's Coral Dev Board based on i.MX8MQ.

https://coral.ai/products/dev-board

The Phanbell naming has been used here to match the naming convention
used in Google's U-Boot source tree:

https://coral.googlesource.com/uboot-imx/



Co-developed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Alifer Moraes <alifer.wsdm@gmail.com>
Tested-by: Marco Franchi <marcofrk@gmail.com>