arm64: dts: imx8mm: Add i.MX8M Mini Toradex Verdin based Menlo board

Add new board based on the Toradex Verdin iMX8M Mini SoM, the MX8Menlo.
The board is a compatible replacement for i.MX53 M53Menlo and features
USB, multiple UARTs, ethernet, LEDs, SD and eMMC.

Reviewed-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Francesco Dolcini <francesco.dolcini@toradex.com>
Cc: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: NXP Linux Team <linux-imx@nxp.com>
To: linux-arm-kernel@lists.infradead.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>