thunderbolt: Restart XDomain discovery handshake after failure

Alex reported that after rebooting the other host the peer-to-peer link
does not come up anymore. The reason for this is that the host that was
not rebooted tries to send the UUID request only 10 times according to
the USB4 Inter-Domain spec and gives up if it does not get reply. Then
when the other side is actually ready it cannot get the link established
anymore. The USB4 Inter-Domain spec requires that the discovery protocol
is restarted in that case so implement this now.

Reported-by: Alex Balcanquall <alex@alexbal.com>
Fixes: 8e1de704 ("thunderbolt: Add support for XDomain lane bonding")
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>