[M] Change in coreboot[main]: Documentation: Add information about the deguard utility

[Nicholas Chin (Code Review)]

Attention is currently required from: Elyes Haouas, Felix Singer, Máté Kukri.

Nicholas Chin has posted comments on this change by Máté Kukri. ( https://review.coreboot.org/c/coreboot/+/84825?usp=email )

Change subject: Documentation: Add information about the deguard utility
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Patch Set 3:

(2 comments)

File Documentation/soc/intel/deguard.md:

https://review.coreboot.org/c/coreboot/+/84825/comment/5b2006e8_394db558?usp... :
PS3, Line 3: "
No matching quote?
```suggestion
Run `git clone "https://review.coreboot.org/deguard%22%60 to get deguard source tree.
```

https://review.coreboot.org/c/coreboot/+/84825/comment/e33320dd_e14453b8?usp... :
PS3, Line 13: bup
Capitalize
```suggestion
After downgrade, we exploit the BUP module of the vulnerable firmware, overwriting the copy of field programmable fuses
```