vl: new runstate transition: RUN_STATE_GUEST_PANICKED -> RUN_STATE_FINISH_MIGRATE

This fixes a problem that after guest panic happens, virsh dump without
--memory-only fails:

ERROR: invalid runstate transition: 'guest-panicked' -> 'finish-migrate'

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1369046780-17498-1-git-send-email-pbonzini@redhat.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
