ASoC: SOF: ipc4-topology: Add support for process modules with no input pins

ASoC: SOF: ipc4-topology: Add support for process modules with no input pins

A tone generator module can be a type of processing module with no input
pins. Adjust the logic to set the reference params for selecting output
format and the basecfg format based on the output format.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20260204081833.16630-7-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>