thunderbolt: Introduce tb_for_each_upstream_port_on_path()

[ Upstream commit 956c3abe ]

This is useful when walking over upstream lane adapters over given path.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Qin Wan <qin.wan@hp.com>
Signed-off-by: Alexandru Gagniuc <alexandru.gagniuc@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>