[BUGFIX] Fix fatal in web->functions for page without access

Resolves: #71767
Releases: master
Change-Id: I0c894ac2edcc3e4c9f24de9dd0f522a310d63526
Reviewed-on: https://review.typo3.org/44887


Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>