root: add mpdecision to system group

Change-Id: Ie46994b9c9d0c00dd1693593d5b9a2e83cd1add3
snd_soc_msm: Correct the default decimator volume

- wcd9310 register dump says that 68 is correct, not 67

Change-Id: I6f1734a1d46b857f9182fc14bc5d67dc68d906c7
Merge "root: add mpdecision to system group" into kk
Merge "snd_soc_msm: Correct the default decimator volume" into kk