x86/kdump: add log before booting crash kernel

euleros inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8RJ7E?from=project-issue


CVE: NA

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Just like arm64, print "Bye!" before booting crash kernel.

Signed-off-by: zhangnaichuan <zhangnaichuan@huawei.com>
Signed-off-by: Bin Wang <wangbin224@huawei.com>