thunderbolt: Do not read control adapter config space

Adapter 0 is the control adapter and as per USB4 spec in section 2.2.6.2
control Adapters do not have an adapter configuration space.

For this reason skip reading adapter config space in tb_port_init() when
the port number is 0. This actually simplifies the rest of the function
as we don't need to check for the port->port == 0 anymore.

While there drop the extra empty line at the end of the function.

Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>