acpi, memory-hotplug: support getting hotplug info from SRAT

acpi, memory-hotplug: support getting hotplug info from SRAT

We now provide an option for users who don't want to specify physical
memory address in kernel commandline.

        /*
         * For movablemem_map=acpi:
         *
         * SRAT:                |_____| |_____| |_________| |_________| ......
         * node id:                0       1         1           2
         * hotpluggable:           n       y         y           n
         * movablemem_map:              |_____| |_________|
         *
         * Using movablemem_map, we can prevent memblock from allocating memory
         * on ZONE_MOVABLE at boot time.
         */

So user just specify movablemem_map=acpi, and the kernel will use
hotpluggable info in SRAT to determine which memory ranges should be set
as ZONE_MOVABLE.

NOTE: Using this way will cause NUMA performance down because the whole node
      will be set as ZONE_MOVABLE, and kernel cannot use memory on it.
      If users don't want to lose NUMA performance, just don't use it.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Wu Jianguo <wujianguo@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Len Brown <lenb@kernel.org>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>