Change in coreboot[master]: soc/intel/common/block/uart: rework to use dummy device

[Nico Huber (Code Review)]

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/48385 )

Change subject: soc/intel/common/block/uart: rework to use dummy device
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Patch Set 3: Code-Review-2

I can't say if this is working, or even if it can work. What
about all the mainboards that use this driver by properly
matching the PCI IDs?

TBH, I don't like to see any more hacks with fake chips or
devices. The old model of attaching drivers via PCI IDs
served us well for a long time. Now Intel makes more and
more PCI devices that actually aren't PCI devices. I think
it's time we adapt and find a new model to attach drivers.

As we have chipset devicetrees now, it makes things easy
to match device drivers by name. Just like we do it for
chip drivers. So my idea would be to do something like
this:

device pci 19.2 hidden
           driver soc/intel/common/block/uart
   end

And then name the `struct pci_driver`
`soc_intel_common_block_uart_driver` accordingly.

Just from the top of my head. Alternative suggestions
are most welcome :)

Another idea to solve one of the issues this chip driver
currently handles: Allow to specify the PCI IDs in the
devicetree if the device is `hidden`.