[BUGFIX] Add module access check to module dispatcher

Recent merges removed the module access check in some
modules while removing the need to have a conf.php file.

This change now adds it to a central place in mod.php
with the benefit that access checks cannot be bypassed
any more not even in third party modules, when using mod.php

Resolves: #63648
Releases: master, 6.2
Change-Id: I5a876a7b46434f5d4c16ff895973826f4066ccab
Reviewed-on: http://review.typo3.org/35137
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Tested-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Reviewed-by: Frank Nägler <typo3@naegler.net>
Tested-by: Frank Nägler <typo3@naegler.net>