PLDM: (MEX LED) Process host state sensor PDRs with state set ID Operational Fault Status

[tomjoseph83]

When processing the FRU Record Set PDRs lookup for state sensors with state set ID OperationalFaultStatus and matching entity information(containerID, entityType and entityInstanceNumber).

Implement xyz.openbmc_project.State.Decorator.OperationalStatus interface and initialize Functional property by reading the sensor value (GetStateSensorReadings).

When the functional status changes on the host ( for example when the FRU goes faulty), host reports it by sending sensorEvent(PlatformEventMessage) to the BMC. Refactor the PlatformEventMessage handler to update the Functional property for the corresponding FRU D-Bus object.

Note: Sensors need not be necessarily related to FRU where PLDM hosts the D-Bus object. There are other sensors which maps to D-Bus property hosted by other OpenBMC applications. The goal should be to write generic code and handle both scenarios.

Related to #2817

[lxwinspur]

review by: https://gerrit.openbmc-project.xyz/c/openbmc/pldm/+/39796