[tools] factorydata encryption

[step0035]

• add option to encrypt factory data with key and iv
• encryption is done automatically via ameba_factory.py script
• add CONFIG_ENABLE_FACTORY_DATA_ENCRYPTION option
• update FactoryData README
  • add instructions for factorydata encryption
  • set protobuf version to 4.21.9
• change the return type of ReadFactory and DecodeFactory to int32_t
• tested commissioning with encrypted factorydata using testnet paa
• update the flash.sh flashing script for flashing factorydata binary