Change in coreboot[master]: mb/prodrive/hermes: Map PCIe clocks to root ports

[Felix Held (Code Review)]

Attention is currently required from: Patrick Rudolph, Christian Walter, Angel Pons.
Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58368 )

Change subject: mb/prodrive/hermes: Map PCIe clocks to root ports
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Patch Set 2:

(1 comment)

File src/mainboard/prodrive/hermes/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/58368/comment/b31d606e_7d85d1a2 
PS2, Line 30: 	register "PcieClkSrcUsage[0]" = "20"		# PCIe Slot1
might be good to have defines or depending on what this actually does an enum in the soc code for those magic values. i'd also avoid mixing decimal numbers and hex numbers for different elements of the same array. feel free to ack this one and address it in a follow-up patch though