mako: enable echo cancellation for voice communication

This greatly improves the quality of VoIP calls, tested on the app
"LINE". Without this, the other party will be able to hear echo
of their own voice.

Reference: http://source.android.com/devices/audio_implement.html#preprocessing

Change-Id: Id0ccb732778ecc8d4c9e140249ec230654f351cc
wlan: Improve W-Fi data transmission stablity

Update gDataInactivityTimeout parameters from 20 to 200ms to improve
wifi throughput when DUT connect to Broadcom solution Mobile Hotspot.

All credits go to XDA-member kalo86
http://forum.xda-developers.com/nexus-4/development/wifi-fix-updated-nexus-4-wireless-t2300873

Change-Id: I6541b439d6aebad5ff8e9b461ceaad7cbd338da7