Multiple entities (e.g. VMBus devices) can use the same SINT route. To
make their lives easier in maintaining SINT route ownership, make it
reference-counted. Adjust the respective API names accordingly.
Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Message-Id: <20180921081836.29230-8-rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>