thunderbolt: Initialize root switch and ports

This patch adds the structures tb_switch and tb_port as well as code to
initialize the root switch.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --cc drivers/thunderbolt/Makefile
Simple merge

diff --cc drivers/thunderbolt/switch.c
Simple merge

diff --cc drivers/thunderbolt/tb.c
Simple merge

diff --cc drivers/thunderbolt/tb.h
Simple merge