Fix in $_protected array of register_globals security procedure

* Followup to b78a8c7d40446a3e2e36772706662fd033fe7d1d
* Just FYI, renamed to "system_path" in 0c1e405437ceb3c1888e151e6a400653310ad6c1
diff --git a/system/core/CodeIgniter.php b/system/core/CodeIgniter.php
index 4f625b1..9df042f 100644
--- a/system/core/CodeIgniter.php
+++ b/system/core/CodeIgniter.php
@@ -89,7 +89,7 @@
 			'_COOKIE',
 			'GLOBALS',
 			'HTTP_RAW_POST_DATA',
-			'system_folder',
+			'system_path',
 			'application_folder',
 			'view_folder',
 			'_protected',