Fix LevelDB maps

src/database-leveldb.cpp

@@ -94,7 +94,7 @@ MapBlock* Database_LevelDB::loadBlock(v3s16 blockpos)
 	std::string datastr;
 	leveldb::Status s = m_database->Get(leveldb::ReadOptions(),
 		i64tos(getBlockAsInteger(blockpos)), &datastr);
-	if (datastr.length() == 0) {
+	if (datastr.length() == 0 && s.ok()) {
 		errorstream << "Blank block data in database (datastr.length() == 0) ("
 			<< blockpos.X << "," << blockpos.Y << "," << blockpos.Z << ")" << std::endl;