Restrict access to Bluetooth system properties

This removes access to Bluetooth system properties from arbitrary
SELinux domains. Access remains granted to init, bluetooth, and
system_app domains. neverallow rules / CTS enforce that access is not
granted to Zygote and processes spawned from Zygote expcept for
system_app and bluetooth.

The reason is that some of these properties may leak persistent
identifiers not resettable by the user.

Test: Bluetooth pairing and data transfer works
Bug: 33700679
Change-Id: Icdcb3927a423c4011a62942340a498cc1b302472