[BUGFIX] Folder: getSubfolders() has no range parameters

Resolves: #41940
Releases: 6.0
Change-Id: Ie45de7e048950cae42672439f72639813ce423ff
Reviewed-on: http://review.typo3.org/15857
Reviewed-by: Steffen Ritter
Tested-by: Steffen Ritter
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Andreas Wolf
Tested-by: Andreas Wolf