[CLEANUP] Use "elseif" instead of "else if"

Change-Id: I837c30b0c9b1f013c4f59a9eb590ed62e3ec8c28
Resolves: #58227
Releases: 6.2
Reviewed-on: https://review.typo3.org/29675
Reviewed-by: Nico de Haen
Tested-by: Nico de Haen