[TASK] Streamline PHP assignments and comments

Use shortening parameters on places that haven't been touched in a while
since PHP 7.0 was a requirement.

Fix PHPdoc comments on various places.

Use booleans instead of integers on variables clearly defined and evaluated
as booleans.

Resolves: #84057
Releases: master
Change-Id: If0ef1a58622a98f4ae5769f953c4c62121abdc89
Reviewed-on: https://review.typo3.org/55915


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Joerg Boesche <typo3@joergboesche.de>
Tested-by: Joerg Boesche <typo3@joergboesche.de>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>