vendor_init can set config.disable_cameraservice

This had been settable by vendors up to and including Q release by
making config_prop avendor_init writeable. We don't allow this any
more. This should be a real vendor settable property now.

Bug: 143755062
Test: adb logcat -b all | grep cameraservice
Test: atest CtsCameraTestCases
Change-Id: Id583e899a906da8a8e8d71391ff2159a9510a630
5 files changed