Add security config for Mink-LOWI Interface Daemon

The Mink-LOWI Interface Daemon (/system/bin/mlid) needs access to
location_socket, and will communicate with privileged apps via a UNIX
domain socket (/dev/socket/mlid) created by init.

mlid must have mlstrustedsubject to allow access by ssg apps.

Change-Id: Ia06d13d63217808684838e293ae88035fbd4ca2e