[L] Change in coreboot[main]: mb/dell/optiplex_9020: Implement late HWM initialization

[Máté Kukri (Code Review)]

Máté Kukri has posted comments on this change by Máté Kukri. ( https://review.coreboot.org/c/coreboot/+/81529?usp=email )

Change subject: mb/dell/optiplex_9020: Implement late HWM initialization
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Patch Set 11:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/81529/comment/6a23a197_424f156d?usp... :
PS11, Line 9: There are 4 different chassis types specified by vendor firmware, each
            : with a slightly different HWM configuration.
> Out of curiosity, where are those specified in the vendor firmware?

I believe the GPIO to chassis type mapping is in "DellChassisConfigDxe".

But to understand the entire HWM configuration and GPIO logic, there are many modules used:
- DxeGpioControl (GPIO abstraction)
- DxeGpioPolicy (GPIO pin definitions)
- DxeSbGpioControl (PCH GPIO driver)
- DxeSioGpioControl (SIO GPIO driver, not implemented in coreboot)
- DellChassisConfigDxe (GPIO -> chassis mapping)
- DxeSioEmi (for talking to the SIO)
- DxeHwmDriver (the actual HWM configuration logic)
- And probably a few more I forgot about.....

I don't think I even have to mention the fact that this is "slightly" over-engineered in the vendor firmware, the length of the above list should make it obvious.