[S] Change in coreboot[main]: util/ifdtool: Add support for checking GPR0 status

[Tyler Wang (Code Review)]

Attention is currently required from: David Wu, Krishna P Bhat D, Reka Norman, Reka Norman, Stefan Reinauer, Subrata Banik.

Tyler Wang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81928?usp=email )

Change subject: util/ifdtool: Add support for checking GPR0 status
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Patch Set 5:

(1 comment)

File util/ifdtool/ifdtool.c:

https://review.coreboot.org/c/coreboot/+/81928/comment/07cc8efa_56162b11 :
PS4, Line 1802: reg.data.write_protect_en
> Yes, that's what I meant. My point is that just because the enable bit is set, it doesn't necessarily mean protection is enabled. E.g. if the range is 0, it's not really enabled.

I'm agree with you. Since the purpose of `is_gpr0_protected()` is to know GPR0 protected is enabled/disabled, so check whole register should be safer.
I will try to do it in `is_gpr0_protected()`, will update once I complete.
> Can I ask what you're planning to use this for? Is it just for developers to use locally, or are you planning to use it in some automated process / test?

It's for developers to use.
Thank you.