Find7: fix headset detection and buttons

Conflicts:
	arch/arm/boot/dts/msm8974.dtsi
	drivers/mfd/wcd9xxx-core.c
	include/linux/mfd/wcd9xxx/pdata.h
	sound/soc/codecs/wcd9320.c
	sound/soc/codecs/wcd9xxx-mbhc.c
	sound/soc/codecs/wcd9xxx-mbhc.h
	sound/soc/msm/msm8974.c