ARM: dts: imx6qdl-zii-rdu2: Specify supplies for accelerometer

Specify 'vdd' and 'vddio' supplies for accelerometer to avoid warnings
during boot.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org,
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>