Change in coreboot[master]: soc/intel/cannonlake: Clear RTC_BATTERY_DEAD

[Nico Huber (Code Review)]

Attention is currently required from: Furquan Shaikh, Tim Wawrzynczak, Patrick Rudolph.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56668 )

Change subject: soc/intel/cannonlake: Clear RTC_BATTERY_DEAD
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Patch Set 1:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/56668/comment/aabe0d15_a2002a1f 
PS1, Line 11: RTC_BATTERY_DEAD
            : is set
Why is that? Is it really always like this after flashing? or is this an `if`?

https://review.coreboot.org/c/coreboot/+/56668/comment/705d770a_4d70a7e7 
PS1, Line 13: which clears RTC_BATTERY_DEAD towards the end of its
            : execution
Is this FSP's only reaction? Doesn't it need to know the failure
state for anything else?