thunderbolt: Improve DisplayPort tunnel setup process to be more robust

After DisplayPort tunnel setup, we add verification that the DPRX
capabilities read process completed. Otherwise, we bail out, teardown
the tunnel, and try setup another DisplayPort tunnel using next
available DP IN adapter. We do so till all DP IN adapters tried. This
way, we avoid allocating DP IN adapter and (bandwidth for it) for
unusable tunnel.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>