KVM: x86: fire timer when it is migrated and expired, and in oneshot mode

commit 8e6ed96c

 upstream.

when the vCPU was migrated, if its timer is expired, KVM _should_ fire
the timer ASAP, zeroing the deadline here will cause the timer to
immediately fire on the destination

Cc: Sean Christopherson <seanjc@google.com>
Cc: Peter Shier <pshier@google.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Link: https://lore.kernel.org/r/20230106040625.8404-1-lirongqing@baidu.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Hunter <david.hunter.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>