Change in coreboot[master]: soc/mediatek: PCI: Assert PERST# at bootblock stage

[Hung-Te Lin (Code Review)]

Attention is currently required from: Shelley Chen, Paul Menzel, Angel Pons, Yu-Ping Wu, Jianjun Wang.
Hung-Te Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62359 )

Change subject: soc/mediatek: PCI: Assert PERST# at bootblock stage
......................................................................

Patch Set 9:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/62359/comment/905d50e7_dd4fca7a 
PS9, Line 14: 100ms
> Agree with Angel's concern. […]

a hacky implementation: we can assume the pre-init should be done very early in the bootblock, for example within 10ms or even 100ms, and then call get_us_since_boot() before next pcie init, to make sure there's enough delay.