MT#56234 add voip_preferences.expose_to_subscriber

* expose_to_subscriber is a new preferences flag that
  indicates that the preference can be read/modified by
  'subscriber' role
* expose_to_customer now only does the same as expose_to_subscriber
  but for 'subscriberadmin' role

Change-Id: I4b38ac5653e7132510354de4fd8b72d010d0ff68

db_scripts/diff/15746.down

@@ -0,0 +1,6 @@
+use provisioning;
+set autocommit=0;
+
+ALTER TABLE voip_preferences DROP COLUMN expose_to_subscriber;
+
+COMMIT;

db_scripts/diff/15746.up

@@ -0,0 +1,9 @@
+use provisioning;
+set autocommit=0;
+
+ALTER TABLE voip_preferences ADD COLUMN expose_to_subscriber tinyint(1) NOT NULL DEFAULT 0;
+
+UPDATE voip_preferences SET expose_to_subscriber = expose_to_customer WHERE expose_to_customer = 1;
+UPDATE voip_preferences SET expose_to_subscriber = 0 WHERE attribute = 'cli';
+
+COMMIT;