Change in coreboot[master]: soc/intel/alderlake: provide a list of D-states to enter LPM

[Subrata Banik (Code Review)]

Attention is currently required from: Tarun Tuli, Paul Menzel.
Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63969 )

Change subject: soc/intel/alderlake: provide a list of D-states to enter LPM
......................................................................

Patch Set 12:

(4 comments)

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

https://review.coreboot.org/c/coreboot/+/63969/comment/632d8ea5_805b05a7 
PS12, Line 179: min_pci_d_states
wondering if we have any way to reduce this static array.

@Tim any-thoughts ?

we could memset to `UNDEF` then only update the relevant index as-applicable for device.

or how about attaching to devicetree.cb that way, only enabled device get the chance to update the `d-states` ?

https://review.coreboot.org/c/coreboot/+/63969/comment/4c3069c0_0fcfba5d 
PS12, Line 470: 
does it make sense to check if device is actually enabled or not ? if not then set to `undef`?

https://review.coreboot.org/c/coreboot/+/63969/comment/a1b742a9_699b991b 
PS12, Line 524: 					if (min_state == UNDEF)
              : 						min_state = D0;
looks like you are setting min_state = D0 for all devices with UNDEF ? in that case, do we still need to initialise the array with UNDEF because by default it still would be `zero` aka D0.

File src/soc/intel/common/block/acpi/pep.c:

https://review.coreboot.org/c/coreboot/+/63969/comment/20faa8f1_44ceee26 
PS12, Line 115: 	/* SoC returned more than zero devices so use those. */
              : 	printk(BIOS_INFO, "Returning SoC specific constraint package for %d devices\n", num_devices)
is this for debug purpose ?