Update src/ipc/readme.md

ipc_get_ppl_comp is described as using “upstream/downstream connection strings”, but the implementation takes a pipeline_id and a direction flag and walks the component/buffer graph (no string-based lookup).

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Liam Girdwood <lgirdwood@gmail.com>

Author: lgirdwood

src/ipc/readme.md

@@ -95,4 +95,4 @@ sequenceDiagram
 ## Global IPC Objects and Helpers
 
 * `ipc_comp_dev`: Wrapper structure linking generic devices (`comp_dev`) specifically to their IPC pipeline and endpoint identifiers.
-* `ipc_get_comp_dev` / `ipc_get_ppl_comp`: Lookup assistants utilizing the central graph tracking to find specific components by ID or relative upstream/downstream connection strings.
+* `ipc_get_comp_dev` / `ipc_get_ppl_comp`: Lookup assistants utilizing the central graph tracking to find specific components either directly by component ID or by traversing the pipeline graph starting from a given `pipeline_id` and direction (upstream/downstream).