[TASK] PATH_site is defined twice in bootstrap

In index.php AND typo3/sysext/cms/tslib/index_ts.php
(which will be included in index.php) the constant
PATH_site is defined.

The definition in typo3/sysext/cms/tslib/index_ts.php
is obsolete, because this will be checked via if(!defined(...)).

See also #35003

Change-Id: Ia0a967f562a2a58655b9db0419654c36e7092a05
Fixes: #35017
Releases: 6.0, 4.7
Reviewed-on: http://review.typo3.org/9753
Reviewed-by: Andy Grunwald
Tested-by: Andy Grunwald
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn

typo3/sysext/cms/tslib/index_ts.php

@@ -63,7 +63,6 @@ if(!defined('PATH_thisScript')) {
 		($_SERVER['ORIG_SCRIPT_FILENAME'] ? $_SERVER['ORIG_SCRIPT_FILENAME'] : $_SERVER['SCRIPT_FILENAME']))));
 }
 
-if (!defined('PATH_site')) 			define('PATH_site', dirname(PATH_thisScript).'/');
 if (!defined('PATH_t3lib')) 		define('PATH_t3lib', PATH_site.'t3lib/');
 
 define('TYPO3_mainDir', 'typo3/');		// This is the directory of the backend administration for the sites of this TYPO3 installation.