x86/topology: use weak version of arch_unregister_cpu()

mainline inclusion
from mainline-v6.8-rc1
commit b0b26bc580de555a504d7eed3866fca607bf1c1f
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8XMTL


CVE: NA

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Since the x86 version of arch_unregister_cpu() is the same as the weak
version, drop the x86 specific version.

Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/E1r5R3r-00Cszs-2R@rmk-PC.armlinux.org.uk


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: liwei <liwei728@huawei.com>