folder dialog: Seems internal TStringList.Sorted removed duplicates
folder dialog: Seems internal TStringList.Sorted removed duplicates

eg: 'Type1' and 'type1' was considered the same directory under
Linux, and only one displayed. This commit fixes the issue and now
all directories are displayed.

wkitty42/fpGUI,wkitty42/fpGUI,wkitty42/fpGUI,wkitty42/fpGUI,wkitty42/fpGUI,wkitty42/fpGUI