Small synch with BASOP, related to BASOP #2235

• Related issues: sa4/audio/ivas-basop#2235 (closed)
• Related BASOP MR: sa4/audio/ivas-basop!2743 (merged)
• Requested reviewers: @janssontoftg

Reason why this change is needed

• There is an unnecessary abs and a comment in the TD renderer code. This cleanup is part of sa4/audio/ivas-basop!2743 (merged) and this is just to keep in synch.

Description of the change

• Remove unnecessary abs and related comment.

Affected operating points

• All BE.