Change in coreboot[master]: soc/intel/common/pmc: Drop redundant pmc_ipc.c entry

[Angel Pons (Code Review)]

Attention is currently required from: Subrata Banik, Maulik V Vaghela, Tim Wawrzynczak, Arthur Heymans, Patrick Rudolph.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59747 )

Change subject: soc/intel/common/pmc: Drop redundant pmc_ipc.c entry
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Patch Set 1: Code-Review+2

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/59747/comment/6c1e02f1_d4bfd2fd 
PS1, Line 7: redundant
Strictly speaking, the removed entry is not redundant, as `pmc_ipc.c` is no longer compiled in when `PMC_IPC_ACPI_INTERFACE` is not enabled.

I'd simply use `unneeded` or `unnecessary` instead.

https://review.coreboot.org/c/coreboot/+/59747/comment/01d1b35b_f3724435 
PS1, Line 9: redundant
Same as above.