audio/msm7627a: Code cleanups, fix potential crashes

Change-Id: I5e75d1fb459d1231279c511d35a0b5d51b5d10e0
audio/msm7627a: Fix mic in Hangouts

 * Add higher sample rates and stereo input to VOIP device

Change-Id: I7b2a439325d1b427cb33b16f3ab5473edc352833
msm7x27a-common: update audio policy config

- add AMR_NB, EVERC AND QCLEP audio format

Change-Id: I8b895f7fc4f22355a8c879ad89818453f4ee826d