[BUGFIX] Variable access instead of function call

Change-Id: I8b840819633e7409ed086e3bf3de0b90aee96b1e
Related: #47162
Fixes: #47165
Releases: 6.1
Reviewed-on: https://review.typo3.org/19847
Reviewed-by: Markus Goldbeck
Tested-by: Markus Goldbeck
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn