ACPI: PPTT: Use acpi_get_cpu_uid() and remove get_acpi_id_for_cpu()

ACPI: PPTT: Use acpi_get_cpu_uid() and remove get_acpi_id_for_cpu()

Update acpi/pptt.c to use acpi_get_cpu_uid() and remove unused
get_acpi_id_for_cpu() from arm64/loongarch/riscv, completing PPTT's
migration to the unified ACPI CPU UID interface

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/20260401081640.26875-8-fengchengwen@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>