New protocol decoder: ds243x

Another protocol decoder recently added to libsigrokdecode is ds243x, which decodes the Maxim/Dallas DS243x 1-Wire EEPROM protocol.

It currently supports the DS2432 (1-Wire 1Kbit protected EEPROM with SHA-1 engine) and the DS2433 (1-Wire 4Kbit EEPROM). Support for additional chips in the same family can be added relatively easily.

The PD stacks on top of the onewire_network decoder (and that one in turn on top of onewire_link).

The protocol decoder was contributed by Kevin Redon (DS2433 support added by Soeren Apel), thanks a lot!