Fix for LTV crash observed for encoder in CI

- xes Encoder original crash for test stream ltv_basop_encoder-OMASA 2TC 3ISM at br sw techs 13.2 to 512 kbps start 24.4 kbps, 32kHz in, 48kHz out, BINAURAL out
- Cause: In inov_encode, the h2 buffer (derived from h1) exceeds Q12 range (>8.0f) in float.
- Fix: Added saturation when scaling h2 to Q12