ipc4: harden IPC4 pipeline triggering logic

[serhiy-katsyuba-intel]

Move two commits out of #10868 as it's not yet clear what to do with the revert there.

ipc4: harden IPC4 pipeline triggering logic
Using IPC4_MOD_ID() is not the best way to check if IPC4 is enabled. For module ID == 0, IPC4_MOD_ID() returns 0 for both IPC3 and IPC4. Module ID 0 is a valid IPC4 BASEFW ID. Since BASEFW is never added to a pipeline, this change doesn't fix any real problem. However, it's just more appropriate and safer to use IS_ENABLED(CONFIG_IPC_MAJOR_4): if module ID data becomes corrupted (zeroed) at runtime, this shouldn't make debugging even harder by causing unexpected pipeline behavior.

ipc4: assert IPC4 pipeline triggering logic
With IPC4, each pipeline is triggered separately. Exactly 1 pipeline is expected in the pipelines list in pipeline_schedule_triggered(). Unfortunately, we still have considerable complex IPC3 pipeline triggering code being used with IPC4. This assertion ensures that the code works correctly for the IPC4 case.

[Copilot]

Pull request overview

This PR hardens IPC4 pipeline trigger handling by removing reliance on IPC4_MOD_ID() as an IPC4/IPC3 discriminator (since module ID 0 is valid in IPC4) and by adding an IPC4-specific assertion to ensure the “single pipeline per trigger” assumption holds.

Changes:

• Replace IPC4_MOD_ID(... ) checks with IS_ENABLED(CONFIG_IPC_MAJOR_4) in several pipeline traversal/trigger/prepare/reset paths to avoid mis-detecting IPC4 when module ID is 0.
• Add an IPC4-only assertion in pipeline_schedule_triggered() to validate that at most one pipeline is present in the scheduled pipelines list for IPC4.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/audio/pipeline/pipeline-stream.c	Avoid IPC4 mis-detection by using a compile-time IPC4 enable check when deciding whether to traverse/trigger connected pipelines.
src/audio/pipeline/pipeline-schedule.c	Use compile-time IPC4 check for STOP-reset behavior; add IPC4-only assertion to validate single-pipeline triggering assumptions.
src/audio/pipeline/pipeline-params.c	Prevent cross-pipeline prepare propagation under IPC4 using IS_ENABLED(CONFIG_IPC_MAJOR_4).
src/audio/pipeline/pipeline-graph.c	Prevent cross-pipeline reset propagation under IPC4 using IS_ENABLED(CONFIG_IPC_MAJOR_4).

[tmleman]

https://github.com/thesofproject/sof/actions/runs/27404363632/job/80989689260?pr=10893

This looks unrelated and I think I've already seen it before (I believe I have a fix on a branch with some other changes). But I will verify it on Monday.