remove bizarre perl detection magic

the code makes no sense, and was added with the QNX port without comment.
there is already a detection a few lines up.

Change-Id: I18ec18604c37c7c42f2649a658dd22324d481dd3
Reviewed-by: Andreas Holzammer <andreas.holzammer@kdab.com>
Reviewed-by: Harald Fernengel <harald.fernengel@nokia.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>