sw64: kvm: fix bad page state setting outside of kvm memory pool

Sunway inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I56WV8



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The page flag of the first page after kvm memory pool is incorrectly
set to "reserved", which will result in page dumped if user try to
apply for it.

Now we exclude the page to fix it.

Signed-off-by: Min Fanlei <minfanlei@wxiat.com>

Signed-off-by: Gu Zitao <guzitao@wxiat.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>