soundwire: stream: don't program mockup device ports

Mockup devices don't take part in command/control operations and their
virtual ports shall not be programmed.

Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Link: https://lore.kernel.org/r/20210714032209.11284-9-yung-chuan.liao@linux.intel.com


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