Don't override the policy files in the local settings

The setting override currently doesn't add anything (the file names are
kept the same) but causes new files added upstream to be missed as the
entire POLICY_FILES dictionary is being overriden.

Change-Id: I2ce4cace705e89ef2fbb4a2f4e57c9074fc512ac
Closes-Bug: #1296636
Merge "Don't override the policy files in the local settings"