vfio: Add Error** argument to .set_dirty_page_tracking() handler

We will use the Error object to improve error reporting in the
.log_global*() handlers of VFIO. Add documentation while at it.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
4 files changed