rephrase option description

db_scripts/diff/13830.up

@@ -4,4 +4,4 @@ select id into @pid from voip_preference_groups where name = 'Internals';
 
 INSERT INTO voip_preferences (attribute, type, dom_pref, usr_pref, peer_pref, data_type,
     max_occur, description, modify_timestamp, voip_preference_groups_id) VALUES('mobile_push_expiry',
-    1, 1, 1, 0, 'int', 1, 'The expiry interval of sent push messages, after expiration of which the client should treat is as outdated and ignore.', '1970-01-01 00:00:00', @pid)
+    1, 1, 1, 0, 'int', 1, 'The expiry interval of sent push request. Client is expected to register within this time, otherwise he should treat the request as outdated and ignore.', '1970-01-01 00:00:00', @pid)