loongarch/kvm: Modify the kvm code style

LoongArch inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8ONTF



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Modify the kvm code style so that script/checkpatch.pl checks can pass.

Signed-off-by: xianglai li <lixianglai@loongson.cn>