arm64/ascend: Add new enable_oom_killer interface for oom contrl

ascend inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8OX3P


CVE: NA

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Support disable oom-killer, and report oom events to bbox
vm.enable_oom_killer:
	0: disable oom killer
	1: enable oom killer (default,compatible with mainline)

Signed-off-by: Weilong Chen <chenweilong@huawei.com>