Eliminate redundant code in greeneye_monitor

[jkeljo]

Proposed change

greeneye_monitor's component setup does a bunch of shuffling around of the configuration that doesn't add a lot of value. We can inline that into the platform setup instead; makes things easier to follow.

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[ctalkington]

needs rebase due to const pull merged

[jkeljo]

Rebased! Thanks for the heads-up.