ARM: dts: imx53: Add power GPIOs on M53Menlo

ARM: dts: imx53: Add power GPIOs on M53Menlo

Add GPIO power button and GPIO poweroff, which is present on new hardware.
These let the system power itself off on shutdown.

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