Change in coreboot[master]: mb/google/brya: Add companion device name to WWAN PCIe generic device

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Bora Guvendik, Cliff Huang, Selma Bensaid.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62330 )

Change subject: mb/google/brya: Add companion device name to WWAN PCIe generic device
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Patch Set 10: Code-Review+1

(1 comment)

File src/mainboard/google/brya/variants/brya0/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/62330/comment/5af09b11_6dc391a9 
PS10, Line 213: rp6_wwan
Oh wait, don't we want
`pcie_rp6`
here?
so that the property is under _SB.PCI0.RP6 ?
It is supposed to be the root port and the device itself, so I would expect RP6 and then _SB.PCI0.RP6.PXSX

I already added support to the WWAN driver itself, see https://review.coreboot.org/c/coreboot/+/62436/4