It makes no sense to hardcode the I2C bus into the codec_name field.

cpu_dai_name and platform_name are also overwritten later in
mxs_sgtl5000_probe_dt().

So remove the three fields, as mxs platform is dt-only platform.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>