[TASK] Avoid foreign_field with select in RootlineUtility

TCA type=select has no config field 'foreign_field'.
A check in RootlineUtility can be simplified a bit.

Resolves: #103647
Releases: main
Change-Id: Ia34a79f1797a9dfb8d9fbadb76d12fd1b2b175b6
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/83845


Tested-by: Nikita Hovratov <nikita.h@live.de>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Jasmina Ließmann <minapokhalo+typo3@gmail.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Nikita Hovratov <nikita.h@live.de>
Reviewed-by: Jasmina Ließmann <minapokhalo+typo3@gmail.com>
Tested-by: core-ci <typo3@b13.com>