[BUGFIX] Use direct method calls for backend layouts in Page Module

Within all refactorings, fetching the correct backend layout and relevant colPos
information was still called via callUserFunction which is not needed at all,
as it is a static information (class + method name) so a regular method call
via PHP works just fine.

Resolves: #90254
Releases: master
Change-Id: I712e86b3a5d343bad3b4752a21dac9cbdc510f46
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/63073


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>