[BUGFIX] No sorting in TypoScript Object Browser when browsing

[BUGFIX] No sorting in TypoScript Object Browser when browsing

If you enable "Sort alphabetically" the correct value (1) is submitted to
extension settings. But when you use any other functionality of the page
(e.g. setting some conditions or use search filter) the value is set to
"on" which disables the sorting.

Change-Id: I88233f94edba032c9b23072fb5e9132b276c8f1e
Fixes: #39677
Releases: 6.0, 4.7, 4.6, 4.5
Reviewed-on: http://review.typo3.org/13567
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn