[BUGFIX] Remove obsolete IRRE-related functions

With the refactoring of client-side IRRE, some functions in TBE_EDITOR
became obsolete. Those are removed now.

Resolves: #88658
Related: #88182
Releases: master
Change-Id: I3e667b70b9108befd88f1a7ee067d73cfffafeb2
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/61196


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Daniel Goerz <daniel.goerz@posteo.de>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Björn Jacob <bjoern.jacob@tritum.de>
Reviewed-by: Daniel Goerz <daniel.goerz@posteo.de>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>