Remove unnecessary overlay

Change-Id: I7f2aa85da2bca82d5c9c273c27bac4766350dbf1
Disable digital noise gate (fixes CYAN-4506).

This fixes CYAN-4505 (Sound cuts out at low volume) [1].
One might think that the digital noise gate (DNG) is better left enabled to
reduce the static noise but in my tests, only the "payload" audio was cut off,
while the static continued. For me it seems that this feature of the sound chip
was not intended for use in a smartphone.

[1]: https://jira.cyanogenmod.org/browse/CYAN-4506.

Change-Id: I4e41c594695f85574ed35e2aef59d6b768403606
galaxys2-common: cleanup tinyalsa audio flag inheritance

also allow r760 to access files

Change-Id: Icd116d6dd47158dd1f61fc8e2b7bd268e1a77210