Change in coreboot[master]: soc/intel/common/smbus: Add `finalize` operation for smbus

[Subrata Banik (Code Review)]

Attention is currently required from: Felix Singer, Tim Wawrzynczak, Arthur Heymans, Nick Vaccaro, Lean Sheng Tan, Eric Lai, Werner Zeh.
Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63640 )

Change subject: soc/intel/common/smbus: Add `finalize` operation for smbus
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Patch Set 5:

(1 comment)

File src/soc/intel/common/block/smbus/smbus.c:

https://review.coreboot.org/c/coreboot/+/63640/comment/e5df13cf_9908f2c8 
PS5, Line 77: tco_lockdown();
> Just curious, we already did the tco lockdown in pch_finalize(), do we need to do it twice? or this is required?

Ideally we want to protect TCO base (fixed IO base) from getting changed during PCI enumeration hence, TCO base lockdown is expected to perform during PCI enumeration. (FSP also does the same as part of NotifyPhase 1). The register attribute is RW, hence no harm of doing it twice as well.

Ideally, I expected to move this into `.final` and drop from `finalize.c` file but we typically have SMBUS device `off` in devicetree, hence, unable to drop from finalize.c file.