Clean up overlays

Change-Id: Idf3aef65055316a32ae9c33eaaad004f175da82b
Add vzw-g2.mk

Reverting audio configuration for vs980, lines 121-131, gets rid of the incall echo for vs980.
Change-Id: I62ac75e9bc26366f7f991652a0aea6648f32b27b