Change in coreboot[master]: [RFC] pc80/rtc/option: Move register backup for SMI

[Kyösti Mälkki (Code Review)]

Attention is currently required from: Angel Pons, Alexander Couzens, Patrick Rudolph.
Kyösti Mälkki has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49253 )

Change subject: [RFC] pc80/rtc/option: Move register backup for SMI
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Patch Set 7:

(2 comments)

File src/drivers/pc80/rtc/option.c:

https://review.coreboot.org/c/coreboot/+/49253/comment/8955332f_8148e208 
PS7, Line 122: 		cmos_backup_idx();
"Datasheet says this register is write-only." Comment from lynxpoint about the CMOS index register pair 0x70/0x72.

File src/southbridge/intel/lynxpoint/smihandler.c:

https://review.coreboot.org/c/coreboot/+/49253/comment/41704a8b_ff85b09a 
PS6, Line 85: 	tmp70 = inb(0x70);
> Datasheet says this register is write-only.

Ack