Since it is now possible to use C++14, it's time to replace
the temporary solution with the standard one

Change-Id: I9a20a58c68d12656359dcaa060d8ab41f621af32
Reviewed-on: https://gerrit.libreoffice.org/66262
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>