Change in coreboot[master]: drivers/intel/dptf: Add OEM variables support

[Sumeet R Pawnikar (Code Review)]

Attention is currently required from: Furquan Shaikh, Justin TerAvest, Tim Wawrzynczak, Todd Broch, Aaron Durbin, Patrick Rudolph, Karthik Ramasubramanian.
Sumeet R Pawnikar has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50127 )

Change subject: drivers/intel/dptf: Add OEM variables support
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Patch Set 10:

(1 comment)

File src/include/acpi/acpigen_dptf.h:

https://review.coreboot.org/c/coreboot/+/50127/comment/0521463c_3c22369f 
PS8, Line 117: 	uint8_t oem0;
             : 	uint8_t oem1;
             : 	uint8_t oem2;
             : 	uint8_t oem3;
             : 	uint8_t oem4;
             : 	uint8_t oem5;
             : };
> Also why is it part of IETM? As per the BWG doc, I don't see any scope being mentioned for ODVP pack […]

I wanted to make simple implementation as per https://review.coreboot.org/c/coreboot/+/54279/1 to define and use these variables under override.