Take `l18n_cfg` into account when fetching pages for PageList

[schloram]

Currently the field l18n_cfg is not taken into account when fetching pages for the PageList CE. This has the effect, that pages where the the Hide default language of page or Hide page if no translation for current language exists checkboxes are set are being fetched as well even though they should not.

I would propose to dump the usage of the DatabaseQueryProcessor for this purpose and and write a custom PageListProcessor. In this processor we could easily make use of methods like \TYPO3\CMS\Frontend\Page\PageRepository::isPageSuitableForLanguage to determine if a page should be rendered in the specific language.