TTS voice packs are better to be common for all devices
So the other device configs can have the common TTS voice packs
for the device build by "gs-common/device.mk"
And see doc, Preload Google Text-to-Speech (TTS) Voice Packs:
The voice packs are dowloanded follow the steps.
Bug: 140145973
Test: build passed and manual test
Change-Id: Ifed0ccecf598c1b09608b45494193524da3b9ed2
e4bfea32c3