[BUGFIX] Fix close link in template module

Sine restyling the backend, the close functionality for constants/setup
does not work anymore. As a solution replace it with a plain link to the
overview.

Change-Id: I006b5e6f59c3e582e1ec3d82fe3aa46e1f8b1b46
Resolves: #63385
Releases: master
Reviewed-on: http://review.typo3.org/34721
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Frans Saris <franssaris@gmail.com>
Tested-by: Frans Saris <franssaris@gmail.com>