[M] Change in coreboot[master]: soc/intel/xeon_sp: Add functions to store/restore uart state in smm

[Angel Pons (Code Review)]

Attention is currently required from: Anjaneya "Reddy" Chagam, Johnny Lin, Christian Walter, Shuming Chu (Shuming), Arthur Heymans.

Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/68567 )

Change subject: soc/intel/xeon_sp: Add functions to store/restore uart state in smm
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Patch Set 4:

(2 comments)

File src/soc/intel/xeon_sp/smihandler.c:

https://review.coreboot.org/c/coreboot/+/68567/comment/f38aed9e_f555cd2c 
PS4, Line 32: 	if (CONFIG(DEBUG_SMI))
This should also depend on `DRIVERS_UART_8250IO`:

if (CONFIG(DRIVERS_UART_8250IO) && CONFIG(DEBUG_SMI))

https://review.coreboot.org/c/coreboot/+/68567/comment/a5e42aad_37749b6d 
PS4, Line 49: 	if (CONFIG(DEBUG_SMI))
This should also depend on `DRIVERS_UART_8250IO`:

if (CONFIG(DRIVERS_UART_8250IO) && CONFIG(DEBUG_SMI))