[CEC Configuration] Move master configuration from '/product/etc' to '/system/etc'

Master configuration should actually be available for all Android devices.

Bug: 168020131
Bug: 174349652
Test: atest HdmiCecConfig; also flashed and smoke tested a device
Change-Id: I79dee4798a4d2405505f58e89d78b152cdc82fd7
4 files changed