ASoC: codecs: es8326: change es8326_regmap_config to static

es8326_regmap_config is only used in es8326.c now, change it to static.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220817091519.2487385-1-yangyingliang@huawei.com


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