mfd: arizona: Add registers for ADC microphone detection

The newer devices support using a software comparison to determine
whether a 3/4 pole jack is present. Add the registers necessary for
this.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>