[S] Change in coreboot[master]: mb/google/skyrim: Hide unused GPP port

[Felix Held (Code Review)]

Attention is currently required from: Martin L Roth, Jason Nien, Eric Lai, Karthik Ramasubramanian.

Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/73862 )

Change subject: mb/google/skyrim: Hide unused GPP port
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Patch Set 1: Code-Review+1

(1 comment)

File src/mainboard/google/skyrim/variants/baseboard/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/73862/comment/97b61d6e_3ac89eb6 
PS1, Line 110: 		device ref gpp_bridge_3 hidden end
> oh, I see it's the FSP different. […]

the chipset devicetree configures the bridges to the different pcie ports as off, but coreboot will complain about leftover devices if it doesn't see the bridge that's being disabled. when the bridge isn't used for an enabled pcie engine in the port descriptor list, the bridge won't show up at all. setting it to hidden in the mainboard code avoids this warning