qemu: Properly propagate migration state to TPM cleanup code

qemu: Properly propagate migration state to TPM cleanup code

When migrating a domain with TPM state on a shared disk, we need to skip
TPM cleanup on both ends. So far the code only handled successful
migration and skipped the cleanup on the source host. But if the
migration failed for some reason, the cleanup would be incorrectly
called on the destination host removing the TPM files even though the
domain was still running on the source host.

https://issues.redhat.com/browse/RHEL-82411

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>