[L] Change in coreboot[main]: mb/amd/birman/devicetree_phoenix_opensil: add stub MPIO chips

[Felix Held (Code Review)]

Attention is currently required from: Fred Reitberger, Jason Glenesk, Matt DeVillier, Varshit Pandya.

Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81101?usp=email )

Change subject: mb/amd/birman/devicetree_phoenix_opensil: add stub MPIO chips
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Patch Set 4:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/81101/comment/9c1966bb_d5112233 :
PS4, Line 22:
> may be add the test info, may be a build check..

only did a build test and no test on real hardware, since this is just the stub. that it compiles is at least to me obvious due to jenkins not complaining (and also having tested that before i pushed), so i don't think that adding that line would add some info