Change in coreboot[master]: src/*acpi: create acpi table for x2apic mode

[Nico Huber (Code Review)]

Attention is currently required from: Furquan Shaikh, Wonkyu Kim, Subrata Banik, Raj Astekar, Patrick Rudolph.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51724 )

Change subject: src/*acpi: create acpi table for x2apic mode
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Patch Set 6:

(2 comments)

File src/acpi/acpi.c:

https://review.coreboot.org/c/coreboot/+/51724/comment/51c46e72_35c34c78 
PS6, Line 165: 			if (apic_ids[index] < 0xff)
No need for further indentation, this could be an `else if`.

https://review.coreboot.org/c/coreboot/+/51724/comment/05a16a09_2c3a27f9 
PS6, Line 170: 	current += acpi_create_madt_lx2apic(
             : 					(acpi_madt_lx2apic_t *)current,
             : 					index, apic_ids[index]);
This already uses the lx2apic function. Please explain what is wrong
with the existing code.