ASoC: codecs: tfa989x: fix register access comments

Fix comments regarding register access based on review feedback[1].

[1]: https://lore.kernel.org/all/YppQ7BiqlBDMNsuc@gerhold.net/



Signed-off-by: Alexander Martinz <amartinz@shiftphones.com>
Link: https://lore.kernel.org/r/20220920115014.952062-1-amartinz@shiftphones.com


Signed-off-by: Mark Brown <broonie@kernel.org>