Change in coreboot[master]: [WIP] cpu/x86: Add Kconfig X2APIC SUPPORT

[Wonkyu Kim (Code Review)]

Attention is currently required from: Kyösti Mälkki.
Wonkyu Kim has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55073 )

Change subject: [WIP] cpu/x86: Add Kconfig X2APIC_SUPPORT
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Patch Set 1:

(1 comment)

Patchset:

PS1: 
Checking x2APIC mode is also in asembly code.
if we want to use Kconfig, we also need to change it.
For detail, refer https://review.coreboot.org/c/coreboot/+/52696/6/src/cpu/x86/smm/smm_stub.S