Change in coreboot[master]: soc/intel/alderlake: Update PMC Descriptor for Alderlake B0 silicon

[Rizwan Qureshi (Code Review)]

Attention is currently required from: Furquan Shaikh, Maulik V Vaghela, Tim Wawrzynczak, Sridhar Siricilla, Patrick Rudolph.
Rizwan Qureshi has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55254 )

Change subject: soc/intel/alderlake: Update PMC Descriptor for Alderlake B0 silicon
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Patch Set 5:

(5 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/55254/comment/a07473db_81e50fd8 
PS3, Line 9: Descriptpr
Descriptor

What is the definition of this field?

https://review.coreboot.org/c/coreboot/+/55254/comment/2caed736_2a769610 
PS3, Line 9: The patch updates PMC Descriptpr which is part of Descriptor Region if
           : system equipped with Alderlake B silicon.
Why are we doing this change, what problem is being fixed?

File src/soc/intel/alderlake/romstage/romstage.c:

https://review.coreboot.org/c/coreboot/+/55254/comment/ccf88a71_cb959c93 
PS4, Line 150: SI_DESC_REGION_SZ
we don't need to read the whole region, we should be fine by just reading the required offset

https://review.coreboot.org/c/coreboot/+/55254/comment/021b0609_d367741f 
PS4, Line 158: SI_DESC_REGION_SZ
just update the offset, as opposed to the entire region

File src/soc/intel/alderlake/romstage/romstage.c:

https://review.coreboot.org/c/coreboot/+/55254/comment/23506474_5ec0d67d 
PS5, Line 132: cse
this doesn't seem to be related to CSE at all
Also, you can just have this check in the calling function itself instead of here.