`kafka_dae_diagnostics`: vetos

[Tom-Willemsen]

kafka_dae_diagnostics needs to handle vetoes:

• good/raw frame counters (whether a frame is good or raw depends on vetoes)
• good/raw uAh
• events should not accumulate into spectrum histogram for a 'raw' frame
• counters/statistics for how many frames were rejected by vetoes

x-ref #15