soundwire: debugfs: add interface for BPT/BRA transfers

soundwire: debugfs: add interface for BPT/BRA transfers

Add code to show what codec drivers will need to do to enable BPT/BRA
transfers. The only difference is to set the 'command_type' file to
'1'. A zero-value will rely on regular read/write commands in Column0.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Tested-by: shumingf@realtek.com
Link: https://lore.kernel.org/r/20250227140615.8147-16-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>