Change in coreboot[master]: cpu/x86/smm,lib/cbmem_console: Enable CBMEMC when using DEBUG_SMI

[Raul Rangel (Code Review)]

Attention is currently required from: Arthur Heymans, Nico Huber, Martin Roth, Tim Wawrzynczak, Julius Werner, Rob Barnes, Karthik Ramasubramanian.
Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62355 )

Change subject: cpu/x86/smm,lib/cbmem_console: Enable CBMEMC when using DEBUG_SMI
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Patch Set 2:

(1 comment)

File src/include/cpu/x86/smm.h:

https://review.coreboot.org/c/coreboot/+/62355/comment/3d60a9ac_f9c35fa5 
PS1, Line 64: void *cbmemc;
            : 	u32 cbmemc_size;
> nit: care to swap those around? That makes the struct entries aligned on 64bit mode. […]

SGTM. I wonder if we should convert `smbase` and `gnvs_ptr` to `void *` in a follow up.