"MachXO2 Programming and Configuration Usage Guide" lists this I2C address with the description, "Resets the device programming/configuration I2C core logic ".

The purpose of this command is to reset the internal I2C command processing FIFO. In the case where a programming/configuration transaction to yyyxxxxx00 was interrupted, the internal I2C FIFO may contain previous transaction data.  Any primary I2C transaction to address yyyxxxxx11 will cause the FIFO to clear.  (The action is keyed to the Slave Address match.  Any following I2C data is ignored.)  Subsequent transactions to address yyyxxxxx00 will be cleanly processed.