FOTA/FUS update script for libprivilege

FOTA/FUS update script for libprivilege

[Issue#]        SSDWSSP-711
[Bug]           Database schema is not updated after FOTA/FUSE system update.
[Cause]         FOTA updates only RO partitions, every RW modifications
                (which are usually done in rmp %post) should be done in
                a dedicated FOTA script.
[Solution]      Added an update script to /etc/opt/upgrade/
[Verification]  Use image with database in version 2 (eg. 20131202).
                (sqlite3 .rules-db.db3 "PRAGMA user_version;")
                Quick verification:
                 - build
                 - install
                 - run /etc/opt/upgrade/220.libprivilege-updater.patch.sh
                Full FOTA verification:
                 - follow instructions from CAM task
                 - database should be upgraded from 2 to 3

Change-Id: Ia6a707443a83bc776545a079bc550b06a5108d44