... in XMLSignatureHelper and XSecController

Change-Id: Ie3817684c9ed9ed8a222e3ba56c8fbc389a68071
Reviewed-on: https://gerrit.libreoffice.org/44193Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>