and just use SvxColorItem in its stead, all of it's special
functionality has been removed over time

Change-Id: I61a4d1fb92d9dccbdfc5bbb6d1a41692b83eb320
Reviewed-on: https://gerrit.libreoffice.org/58938
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>