MDL-69050 lang: Fix few remaining places spotted during integration

admin/tool/dbtransfer/locallib.php

@@ -142,7 +142,7 @@ function tool_dbtransfer_get_drivers() {
         $dblibrary = $matches[2];
 
         if ($dbtype === 'sqlite3') {
-            // Blacklist unfinished drivers.
+            // The sqlite3 driver is not fully working yet and should not be returned.
             continue;
         }
 

mnet/xmlrpc/serverlib.php

@@ -257,7 +257,7 @@ function mnet_server_dispatch($payload) {
     // $method is something like: "mod/forum/lib.php/forum_add_instance"
     // $params is an array of parameters. A parameter might itself be an array.
 
-    // Whitelist characters that are permitted in a method name
+    // Check that the method name consists of allowed characters only.
     // The method name must not begin with a / - avoid absolute paths
     // A dot character . is only allowed in the filename, i.e. something.php
     if (0 == preg_match("@^[A-Za-z0-9]+/[A-Za-z0-9/_\.-]+(\.php/)?[A-Za-z0-9_-]+$@",$method)) {