ARM: dts: imx6q-b850v3: Remove #address/#size-cells from stdp2690

Remove unnecessary #address-cells/#size-cells to fix the following
DTC warnings:

arch/arm/boot/dts/imx6q-b850v3.dtb: Warning (avoid_unnecessary_addr_size): /soc/aips-bus@2100000/i2c@21a4000/mux@70/i2c@1/stdp2690@72: unnecessary #address-cells/#size-cells without "ranges" or child "reg" property
arch/arm/boot/dts/imx6q-b850v3.dtb: Warning (avoid_unnecessary_addr_size): /soc/aips-bus@2100000/i2c@21a4000/mux@70/i2c@1/stdp4028@73: unnecessary #address-cells/#size-cells without "ranges" or child
"reg" property

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>