I would rather recommend using the dedicated Apalis DAP1 aka digital audio pins on the MXM3 pins 194, 196, 198, 200, 202 and 204 for your purpose. This way your design is future prove and any Apalis module should be able to drive your audio codec.
As for the device tree changes this involves 2 distinct areas:
- The pin muxing aka pinctrl (e.g. similar to this)
- The particular codec configuration (e.g. similar to this)
Please have a look at the following article concerning device tree customisation in general.
Plus you may need to enable your particular codecs driver to be included in the kernel.