arm64: dts: imx8mm-evk: Adjust i2c nodes following alphabetical sort

The iomuxc node is being put at end of file because of its huge
pinctrl data. I2C devices should be placed in alphabetical sort.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>