hw: FMC_PG_C2M connected to FPGA only

This Power Good signal from Carrier to Module, FMC_PG_C2M is tied to the FPGA only, so it doesn't necessarily mean the power rails to the FMC are in range, unless the gateware is performing such a check (not the case today). Should this signal instead be connected to the power sequencer?

Somehow related, a strategy (and gateware implementation) for the EN_P1V8_FMC signal is missing.

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Actually, on a 2nd though, these 2 signals are related: FMC_PG_C2M can only go high once EN_P1V8_FMC is asserted (and the voltage is within bounds). So either FMC_PG_C2M is connected to the 1V8 buck's PG or the gateware performs such a check before asserting FMC_PG_C2M. Currently I've just tied both signals to high in the gateware, just to get things working.