thunderbolt: Pass metadata directly to usb4_switch_op()

We are going to make usb4_switch_op() to match better the corresponding
firmware (ICM) USB4 router operation proxy interface, so that we can use
either based on the connection manager implementation. For this reason
pass metadata directly to usb4_switch_op().

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