Change in coreboot[master]: soc/mediatek: Fix null pointer dereference error when PCIe link down

[Jianjun Wang (Code Review)]

Attention is currently required from: Hung-Te Lin, Yu-Ping Wu.
Jianjun Wang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62673 )

Change subject: soc/mediatek: Fix null pointer dereference error when PCIe link down
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Patch Set 1:

(1 comment)

Patchset:

PS1:
> Is it a common scenario that PCIe link will go down?

Sort of, SSD card broken or not connected will cause PCIe link down, the only common scenario that I can think of is we add the PCIe domain in devicetree.cb, but choose eMMC boot and the SSD card is not connected.