ASoC: ak5558: Fix s/show/slow/ typo

s/show/slow/

Fixes: 92088477 ("ASoC: ak5558: Add support for AK5558 ADC driver")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1617458365-23393-1-git-send-email-shengjiu.wang@nxp.com


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