NOJIRA: Fix the OT-RCP builds

[chirag-silabs]

Issue Link:
NA

Description of Problem/Feature:
The OT-RCP builds are failing due to the rename of the path in the SiSDK

Description of Fix/Solution:
Correcting the path in the ot-rcp script with the latest SiSDK

Testing Done:
Ran the script locally

[cursor]

PR Summary

Low Risk
Single build-script path change with no runtime, security, or product logic impact.

Overview
Updates build_ot_rcp.py so slc generate points at the OpenThread RCP project under the renamed SiSDK tree.

The slcp_file_path segment changes from openthread_app/ot-ncp/ot/ot-rcp.slcp to thread_app/ot-ncp/ot/ot-rcp.slcp, matching the current SDK layout and restoring OT-RCP binary builds that were failing on the old path.

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[Rohan Sahay (rosahay-silabs)]

LGTM

Just curious was this change done recently? and do we have any checks in the CICD to identify path changes?
Just a suggestion, we should have a sanity check for checking for filepaths and not build the project, to bring out such misses earlier.

[sarthak shaha (Sarthak-Shaha)]

LGTM

Just curious was this change done recently? and do we have any checks in the CICD to identify path changes? Just a suggestion, we should have a sanity check for checking for filepaths and not build the project, to bring out such misses earlier.

They made the change for 26Q4 release,
We only run ot-rcp as manual trigger and hence not caught earlier.