sw64: kvm: add guest live migration support

Sunway inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5XTKO



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This patch adds live migration support for guest os. It requires
hmcode of host and guest to be upgraded to activate this feature.

Signed-off-by: Min Fanlei <minfanlei@wxiat.com>
Reviewed-by: He Sheng <hesheng@wxiat.com>
Signed-off-by: Gu Zitao <guzitao@wxiat.com>