Commit 54aa3de7 switched multiple sites to use QAPI_LIST_PREPEND
instead of open-coding, but missed a couple of spots.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210113221013.390592-3-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>