soundwire: stream: use consistent pattern for freeing buffers

The code should free the message buffer used for data, the message
structure used for control and assign the latter to NULL. The last
part is missing for multi-link cases, and the order is inconsistent
for single-link cases.

Link: https://github.com/thesofproject/linux/issues/4056


Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20230119073211.85979-2-yung-chuan.liao@linux.intel.com


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