[CLEANUP] Review comment and sig of checkRootlineForIncludeSection()

Reviews the comments and signatures of:

TypoScriptFrontendController::checkRootlineForIncludeSection()
TypoScriptFrontendController::checkPagerecordForIncludeSection()

Casts the return values to bool.

Resolves: #81280
Releases: master
Change-Id: I9344e2f3bcfeed12af7e51e0a50b07631eb1d33f
Reviewed-on: https://review.typo3.org/52895


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>