SELinux policy for new managed system update APIs

We introduced a new API to allow Device Owner to install an OTA file on disk.
This in turn requires system_server to be able to copy the OTA file to a known
OTA file location, call into update_engine to start the installation and let
update_engine to call back to the system_server to deliver any error conditions
asynchronously. This CL modifies the SELinux policy to allow these interaction.

Test: manual in TestDPC, CTS tests for negative cases: atest com.android.cts.devicepolicy.DeviceOwnerTest#testInstallUpdate
Change-Id: Id1fbea9111f753c5c80f270c269ecb9ef141cd79
Bug: 111173669