Change in coreboot[master]: drivers/pcie/rtd3/device: Add PCIe RTD3 driver

[Raul Rangel (Code Review)]

Attention is currently required from: Jason Glenesk, Furquan Shaikh, Marshall Dawson, Tim Wawrzynczak, Karthik Ramasubramanian, Felix Held.
Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54966 )

Change subject: drivers/pcie/rtd3/device: Add PCIe RTD3 driver
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Patch Set 4:

(1 comment)

File src/soc/amd/common/block/rtd3/rtd3.c:

https://review.coreboot.org/c/coreboot/+/54966/comment/cded111f_fde07438 
PS1, Line 210: pci_dev_read_resources
> I would just write into that device's scope, regardless. […]

What about the NVMe case where we don't have a PCI driver that writes the ACPI node?

device ref gpp_bridge_3 on
    	device pci 00.0 alias nvme on end

# Required so the NVMe gets placed into D3 when entering S0i3.
    	chip drivers/pcie/rtd3/device
    		use nvme as target
    		register "reset_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_LOW(GPIO_40)"
    		register "reset_delay_ms" = "100"
    		register "reset_off_delay_ms" = "1"
    		device generic 0 on end
    	end
    end # NVMe

In this case we never write a PCI ACPI Device node.