dt-bindings: arm: fsl: Add devicetree binding for M53 Menlo board.

Add devicetree binding for iMX53 SoC based M53 Menlo board.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Rob Herring <robh@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: devicetree@vger.kernel.org
To: linux-arm-kernel@lists.infradead.org
Signed-off-by: Shawn Guo <shawnguo@kernel.org>