[S] Change in coreboot[main]: acpi/acpi_gic: Add GIC ITS subtable

[Arthur Heymans (Code Review)]

Attention is currently required from: Angel Pons, Cliff Huang, Lance Zhao, Maximilian Brune, Naresh Solanki, Nico Huber, Patrick Rudolph, Paul Menzel, Tim Wawrzynczak.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78115?usp=email )

Change subject: acpi/acpi_gic: Add GIC ITS subtable
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Patch Set 4:

(3 comments)

File src/acpi/acpi_gic.c:

https://review.coreboot.org/c/coreboot/+/78115/comment/f45204c6_7452fe18 :
PS4, Line 85: }
> Is this weak implementation necessary? The other platform_*() functions
> above don't have one.

Would it make sense to the ITS to the devicetree and just loop over them?

https://review.coreboot.org/c/coreboot/+/78115/comment/1a871698_9313498d :
PS4, Line 99: its_base + (i * its_size);
This API is strange and possibly not sufficiently generic. It looks like the its_size is just there for some SOC specific alignment or spacing between ITS, but it still assumes that they are placed sequentially in memory. Why not pass an array of bases in platform_get_gic_its and their count?

File src/include/acpi/acpi.h:

https://review.coreboot.org/c/coreboot/+/78115/comment/7add6a4d_457d8851 :
PS4, Line 1600: uintptr_t
size_t