ASoC: cs42l56: remove unused variable 'adc_swap_enum'

sound/soc/codecs/cs42l56.c:206:30: warning:
 adc_swap_enum defined but not used [-Wunused-const-variable=]

It is never used, so can be removed.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20190815092436.34632-1-yuehaibing@huawei.com


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