[consortium-v1] Get list validators from genesis instead of statedb for snapsync.

[huyngopt1994]

Related to recent PR merged to path-base implementing #614

State sync overwrites the persistent state, and this action can disrupt states that reference the current persistent state. The appropriate solution in such a situation is to mark the entire trie database as unusable, which prevents any subsequent state reads, and raises a layer stale error if the read operation is done by the prev-created stale state. The trie database will remain in this state until the state sync process is completed, and a usable persistent state is assembled.

In the coming enhancements related to avoid disruption genesis data in the snap sync with path schem enable. In the Ronin implementing, we have some functions for getting Validators from StateDB during snap sync which violate this approach.

	// set SCValidators function before initiating new miner to prevent miner starts without SCValidators
	if chainConfig.Consortium != nil {
		c := eth.engine.(*consortium.Consortium)
		stack.RegisterAPIs(c.APIs(eth.blockchain))
		c.SetGetSCValidatorsFn(func() ([]common.Address, error) {
			stateDb, err := eth.blockchain.State()
			if err != nil {
				log.Crit("Cannot get state of blockchain", "err", err)
				return nil, err
			}
			return state.GetSCValidators(stateDb), nil
		})

---

	if mode == SnapSync {
		if !d.snapSync {
			// Snap sync will directly modify the persistent state, making the entire
			// trie database unusable until the state is fully synced. To prevent any
			// subsequent state reads, explicitly disable the trie database and state
			// syncer is responsible to address and correct any state missing.
			if d.blockchain.TrieDB().Scheme() == rawdb.PathScheme {
				if err := d.blockchain.TrieDB().Disable(); err != nil {
					return err
				}
			}

[minh-bq]

nit: In the commit message, can we have commit title + newline + commit description? Right now we have commit title + commit description without newline in between.