arm64: defconfig: Enable memory hotplug and hotremove config

Let's enable ACPI_HMAT, ACPI_HOTPLUG_MEMORY, MEMORY_HOTPLUG
and MEMORY_HOTREMOVE for more test coverage, also there are
useful for heterogeneous memory scene.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220629093524.34801-1-wangkefeng.wang@huawei.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>