[S] Change in coreboot[master]: acpi.c: Fill in >4G FADT entries correctly

[Nico Huber (Code Review)]

Attention is currently required from: Arthur Heymans, Felix Held, Lance Zhao, Tim Wawrzynczak.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/76179?usp=email )

Change subject: acpi.c: Fill in >4G FADT entries correctly
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Patch Set 3:

(3 comments)

File src/acpi/acpi.c:

https://review.coreboot.org/c/coreboot/+/76179/comment/e05f75c6_da2538d8 :
PS3, Line 1730: <
Nit, technically `<=`. But in practice it has to be lower
(`<= UINT32_MAX - alignment + 1`) anyway.

https://review.coreboot.org/c/coreboot/+/76179/comment/cb7981bf_845d0e69 :
PS3, Line 1731: unsigned long
Make it `uintptr_t` while we are at it? It's always the same as
`unsigned long` in coreboot, that's why the cast works currently.

https://review.coreboot.org/c/coreboot/+/76179/comment/7f995b75_17bdf47a :
PS3, Line 1733: 	fadt->x_firmware_ctl_h = (uint32_t)((uintptr_t)facs >> 32);
Regarding `-Wshift-count-overflow`, maybe it's best to put everything on
if/else branches. (/me doesn't like warning overrides, but that's also
a possible solution)