DOCX/DOCM uses com.sun.star.comp.oox.FormatDetector for filter
detection, this one is unused.

Change-Id: I01776d130b0f8f0a75ee39a0cfbf974639c94216
Reviewed-on: https://gerrit.libreoffice.org/38800Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>