t0lte: user configureable voice/streaming volumes [2/2]

relies on http://review.cyanogenmod.org/#/c/43834/

Change-Id: I03367bf0424257d906a6c8e059e4ca6d9faa7dec
smdk4412-common: add i925

Change-Id: I51904c07a881e3c8e4470bbfedda25cefd62b9f4