[M] Change in coreboot[master]: mb/intel/mtlrvp: Add MTL-P RVP board ids

[Harsha B R (Code Review)]

Attention is currently required from: Wonkyu Kim, Ravishankar Sarawadi, Rizwan Qureshi, Angel Pons, Krishna P Bhat D, Tim Wawrzynczak, Tarun Tuli, Jamie Ryu, Subrata Banik, Kapil Porwal, Nick Vaccaro, Ronak Kanabar, Raj Astekar.

Harsha B R has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/66102 )

Change subject: mb/intel/mtlrvp: Add MTL-P RVP board ids
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Patch Set 15:

(1 comment)

File src/mainboard/intel/mtlrvp/board_id.c:

https://review.coreboot.org/c/coreboot/+/66102/comment/c8f03119_eb8190b9 
PS4, Line 10:
> Since the requested code changes will be addressed later (as part of cros_bug), please do help in re […]

Created CB:70227 addressing the common code for board_id specific implementation