[coreboot-gerrit] Change in coreboot[master]: acpigen,cpu/intel/common: rework detecting static DWORDs in CPPC table

[Tim Wawrzynczak (Code Review)]

Attention is currently required from:  Felix Singer, Matt Delco, Nico Huber, Furquan Shaikh, Tim Wawrzynczak, Paul Menzel, Angel Pons, Subrata Banik, Michael Niewöhner, Kyösti Mälkki, Patrick Rudolph.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/57886 )

Change subject: acpigen,cpu/intel/common: rework detecting static DWORDs in CPPC table
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Patch Set 4:

(1 comment)

Patchset:

PS3:
> > Add a type to the CPPC entry, i.e. (ADDR, DWORD). […]

A simple tagged union is all you need here, e.g.:
```
struct cppc_entry {
        enum { ADDR, DWORD } type;
        union {
                acpi_addr_t addr;
                uint32_t dword;
        };
};
```

No need to transform it then:
```
if (entry->type == ADDR) 
       acpigen_write_register_resource(&entry->addr);
```