This is the interface for querying file recovery information for all exited storage miners.
// QueryAllRestoralTarget query the data recovery information of all exited storage miner
// - block: block number, less than 0 indicates the latest block
//
// Return:
// - []RestoralTargetInfo: all the data recovery information
// - error: error message
func (c *ChainClient) QueryAllRestoralTarget(block int32) ([]RestoralTargetInfo, error)