ASoC: rt5677: rt5677_irq_init() can be static

sound/soc/codecs/rt5677.c:4017:5: sparse: symbol 'rt5677_irq_init' was not declared. Should it be static?
sound/soc/codecs/rt5677.c:4044:6: sparse: symbol 'rt5677_irq_exit' was not declared. Should it be static?

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>