blockdev: transaction: refactor handling transaction properties Only backup supports GROUPED mode. Make this logic more clear. And avoid passing extra thing to each action. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20230510150624.310640-5-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>