Change in coreboot[master]: soc/mediatek: Add PCIe support

[Angel Pons (Code Review)]

Attention is currently required from: Hung-Te Lin, Furquan Shaikh, Paul Menzel, Jianjun Wang.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56791 )

Change subject: soc/mediatek: Add PCIe support
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Patch Set 6:

(1 comment)

File src/soc/mediatek/common/pcie.c:

https://review.coreboot.org/c/coreboot/+/56791/comment/73398adf_bd162bc7 
PS6, Line 111: 	mdelay(100);
> That’s pretty long for coreboot.

One way to avoid this delay would be to assert PERST# earlier, and do something else in the meantime. For instance, assert PERST# before memory init.