[TASK] Remove locale-workaround for PHP before 5.5

Since CMS 7 requires at least PHP 5.5 we can remove a
workaround for a bug with turkish locales.
According to the bugreport this is fixed since the 5.5-branch:
https://bugs.php.net/bug.php?id=18556

Change-Id: I905f1c4efda8ea10b615c65d13289cfa596785f3
Resolves: #63288
Releases: master
Reviewed-on: http://review.typo3.org/34536
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Reviewed-by: Benjamin Mack <benni@typo3.org>
Reviewed-by: Stefan Froemken <froemken@gmail.com>
Tested-by: Markus Klein <klein.t3@reelworx.at>
Reviewed-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Tested-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Tested-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>