ACPI GNVS: Drop most dev_count_cpu()

Only amd/picasso and amd/stoneyridge have reference to
PCNT and that could be replaced with acpigen.

Remove the PCNT name from GNVS OperationRegion elsewhere.

Change-Id: I7dd45a840b3585fd24c31fd923b991c34ab4d783
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49272
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/soc/intel/broadwell/pch/lpc.c

@@ -604,9 +604,6 @@ void soc_fill_gnvs(struct global_nvs *gnvs)
 {
 	/* Set unknown wake source */
 	gnvs->pm1i = -1;
-
-	/* CPU core count */
-	gnvs->pcnt = dev_count_cpu();
 }
 
 static unsigned long broadwell_write_acpi_tables(const struct device *device,