zink: clear descriptor refs on buffer replacement
the bo here can only ever be destroyed before it gets reused, so prune it from the descriptor cache immediately
Reviewed-by: Dave Airlie airlied@redhat.com Part-of: !13350 (merged)
the bo here can only ever be destroyed before it gets reused, so prune it from the descriptor cache immediately
Reviewed-by: Dave Airlie airlied@redhat.com Part-of: !13350 (merged)