Move props out of exported3_system_prop

This is to remove bad context name "exported3_system_prop".

- persist.sys.device_provisioned -> provisioned_prop
- sys.retaildemo.enabled -> retaildemo_prop

Bug: 154885206
Test: boot device and see no denials
Change-Id: Ia19a19d93d0689deb56d66fe0b039ace44e4836f
7 files changed