MDL-61658 user: Fix displaying of user's country name

In these cases we want to use the method get_list_of_countries() to
obtain translated names of all potential country codes. The country code
is already there in the database. So it does not matter if the country
is among those whitelisted in $CFG->allcountrycodes - we want to see its
name anyway.

admin/user.php

@@ -252,7 +252,7 @@
 
     } else {
 
-        $countries = get_string_manager()->get_list_of_countries(false);
+        $countries = get_string_manager()->get_list_of_countries(true);
         if (empty($mnethosts)) {
             $mnethosts = $DB->get_records('mnet_host', null, 'id', 'id,wwwroot,name');
         }