... so just ignore all clipPath until its support is implemented in filter/source/svg/

Regression introduced by 3056a6b6.
Verified that tdf#95332 and tdf#65864 are still rendered correctly

Change-Id: Ie3bdee545a81554ef2a95d373e2559e2540ddaa5
Reviewed-on: https://gerrit.libreoffice.org/19889Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>