soundwire: bus: set initial value to port_status

port_status[port_num] are assigned for each port_num in some if
conditions. So some of the port_status may not be initialized.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190829181135.16049-1-yung-chuan.liao@linux.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>