Change in coreboot[master]: soc/intel/graphics: Add override api for graphics_get_memory_base()

[Ethan Tsao (Code Review)]

Attention is currently required from: Subrata Banik, Nico Huber, Ravishankar Sarawadi, Tim Wawrzynczak, Paul Menzel, Raj Astekar, Patrick Rudolph.
Ethan Tsao has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/61389 )

Change subject: soc/intel/graphics: Add override api for graphics_get_memory_base()
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Patch Set 8:

(1 comment)

Patchset:

PS7:
> Can somebody tell me how the new version of the function will […]

memory base can't be extracted directly from PCI config value like common code and based on mapping by Graphic design.