[ranj063]

When there are shared pipelines between multiple PCMs, the triggering of pipeline states needs to be synchronized with the number of active PCMs that are using it. So we introduce a struct snd_sof_pipeline that can hold the information about how many PCMs are using the PCMs at any given time (started_count) and how many are paused (paused_count).

The started_count keeps track of the count of PCMs that are using a pipelines (including the ones that are paused). The paused_count keeps track of the PCM's that are using the pipeline but are paused. So there are 3 simple rules:

1. A pipeline should be paused when all PCMs using it are paused.
2. A pipeline should be set to RUNNING if it was never started or if all PCMs using it were previously paused
3. A pipeline should be set to RESET if no PCM is using the pipeline ie when the started_count and paused_count are both 0