[M] Change in coreboot[master]: util/apcb: Add apcb edit tool for phoenix

[Karthik Ramasubramanian (Code Review)]

Attention is currently required from: Martin L Roth, Raul Rangel, Rob Barnes.

Karthik Ramasubramanian has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/76188?usp=email )

Change subject: util/apcb: Add apcb edit tool for phoenix
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Patch Set 2:

(3 comments)

File util/apcb/apcb_v3a_edit.py:

https://review.coreboot.org/c/coreboot/+/76188/comment/d18e6746_b6e402fb :
PS2, Line 18: spd_block_header = namedtuple(
            :     'spd_block_header', 'Type, Length, Key, Reserved')
Interesting that there is no block ID in the header. I thought there was block ID. This will help to ensure that we are injecting the block at the right spot.

https://review.coreboot.org/c/coreboot/+/76188/comment/2d3a590b_0f31c9bf :
PS2, Line 96: if b in ZERO_BLOCKS: continue
The code asserts that it is zero block in our SPD. Should it also assert that it is zero block in APCB's SPD too or does APCB not contain zero blocks?

https://review.coreboot.org/c/coreboot/+/76188/comment/e4293951_27caf40b :
PS2, Line 120: assert len(apcb) == apcb
Just curious whether we need to assert every time a block is injected. I see that you are asserting the final APCB length after injecting all SPDs in line 130.