[M] Change in coreboot[main]: cpu/x86/smm: Make SMM stub x86_32 only

[Shuo Liu (Code Review)]

Attention is currently required from: Jérémy Compostella, Patrick Rudolph.

Shuo Liu has posted comments on this change by Patrick Rudolph. ( https://review.coreboot.org/c/coreboot/+/87177?usp=email )

Change subject: cpu/x86/smm: Make SMM stub x86_32 only
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Patch Set 6: Code-Review+1

(3 comments)

File src/cpu/x86/mp_init.c:

https://review.coreboot.org/c/coreboot/+/87177/comment/6e6b41b8_10a499b8?usp... :
PS6, Line 34: asmlinkage void __prot2lm_smm_do_relocation(void *arg);
Should these be put into header files?

File src/cpu/x86/smm/smm_module_handler.c:

https://review.coreboot.org/c/coreboot/+/87177/comment/00acd810_8d9158c9?usp... :
PS6, Line 209: RMODULE_ENTRY(smm_handler_start);
It would be helpful if mentioning the file name smm_module_entry.S for ENV_X86_64 here.

File src/cpu/x86/smm/smm_stub.S:

https://review.coreboot.org/c/coreboot/+/87177/comment/8ff53fc4_a931a69f?usp... :
PS6, Line 199: 	push	%ebx /* uintptr_t *canary */
If the handler is x32, should we comment uint32_t instead of uintptr_t here and drop the padding?