ASoC: SOF: ipc4-pcm: Adjust pipeline_list->pipelines allocation type

ASoC: SOF: ipc4-pcm: Adjust pipeline_list->pipelines allocation type

In preparation for making the kmalloc family of allocators type aware,
we need to make sure that the returned type from the allocation matches
the type of the variable being assigned. (Before, the allocator would
always return "void *", which can be implicitly cast to any pointer type.)

The assigned type is "struct snd_sof_pipeline **", but the returned type
will be "struct snd_sof_widget **". These are the same size allocation
(pointer size) but the types don't match. Adjust the allocation type to
match the assignment.

Signed-off-by: Kees Cook <kees@kernel.org>
Fixes: 9c04363d222b ("ASoC: SOF: Introduce struct snd_sof_pipeline")
Acked-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://patch.msgid.link/20250426062511.work.859-kees@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>