arm64: Add CONFIG_IPI_AS_NMI to IPI as NMI feature

maillist inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8PLUM
CVE: NA
Reference: https://lore.kernel.org/all/1604317487-14543-2-git-send-email-sumit.garg@linaro.org/



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This patch adds CONFIG_IPI_AS_NMI to control the availability of
pseudo NMIs, which follows upstream commit 41ddf73f (arm64: Add
framework to turn IPI as NMI).

Signed-off-by: Liao Chen <liaochen4@huawei.com>