ASoC: fsl_sai: Add support for i.MX8MM

On i.MX8MM the max register is FSL_SAI_MCTL, which is
different with previous platform, so add max_register in
soc data to distinguish platforms.
And add specific soc data for i.MX8MM

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/1652688372-10274-2-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>