[S] Change in coreboot[master]: soc/amd/mendocino: Force resets to be cold

[Tim Van Patten (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Martin L Roth, Matt DeVillier, Fred Reitberger, Felix Held.

Tim Van Patten has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/72486 )

Change subject: soc/amd/mendocino: Force resets to be cold
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Patch Set 3:

(1 comment)

File src/soc/amd/mendocino/fch.c:

https://review.coreboot.org/c/coreboot/+/72486/comment/919e6bf2_4ffd90f5 
PS3, Line 131: 	pm_write16(PWR_RESET_CFG, pm_read16(PWR_RESET_CFG) | TOGGLE_ALL_PWR_GOOD);
> fch_init_resets() is there so that when Linux does a reset, it's a cold reset.  This is identical to the situation on Cezanne.  If it's not there, the system will hang on reboot after S0i3.
> The warm resets in coreboot haven't been an issue, and we could probably leave that part of this change out, but it definitely doesn't hurt to have it in there as well.

Please update the commit message to clarify this.