As a start just make sure we accept "ETSI.CAdES.detached" as a valid
SubFilter value.

Change-Id: I19f480a5a24df0f451261d6d9a0dd9bd72ff6cc1
Reviewed-on: https://gerrit.libreoffice.org/31414Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>