[Non-BE] Resolve "Assert in stereo ICA encoder"

• Related issues: #2599 (closed)
• Requested reviewers: @norvell

Reason why this change is needed

Assert in stereo ICA encoder

Description of the change

Using _sat where needed

Affected operating points

• Stereo input with high level, but seems to be a corner-case.

Closes #2599 (closed)