Instead of allowing global read access to all properties,
only allow read access to the properties which are part of
core SELinux policy. Device-specific policies are no longer
readable by default and need to be granted in device-specific
policy.

Grant read-access to any property where the person has write
access. In most cases, anyone who wants to write a property
needs read access to that property.

Change-Id: I2bd24583067b79f31b3bb0940b4c07fc33d09918