ACPI: processor: Simplify initial onlining to use same path for cold and hotplug

ACPI: processor: Simplify initial onlining to use same path for cold and hotplug

Separate code paths, combined with a flag set in acpi_processor.c to
indicate a struct acpi_processor was for a hotplugged CPU ensured that
per CPU data was only set up the first time that a CPU was initialized.
This appears to be unnecessary as the paths can be combined by letting
the online logic also handle any CPUs online at the time of driver load.

Motivation for this change, beyond simplification, is that ARM64
virtual CPU HP uses the same code paths for hotplug and cold path in
acpi_processor.c so had no easy way to set the flag for hotplug only.
Removing this necessity will enable ARM64 vCPU HP to reuse the existing
code paths.

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Miguel Luis <miguel.luis@oracle.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20240529133446.28446-2-Jonathan.Cameron@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>