Decoder crash for stereo at 48 kbps JBM processing decoding to Mono
# Basic info
<!--- Add commit SHA used to reproduce -->
- Float reference:
- Encoder (float): dd0cceede1515e223b0e70cb3bf84389289bb396
- Fixed point:
- Decoder (fixed): 6835cac606d32cdb27f1fa671dcbb0946c2b5dda
# Bug description
The fixed point decoder crashes with an assert:
```
Frames processed: 3326 Assertion failed: (0), function saturate, file basop32.c, line 483.
```
{width=327 height=231}
# Ways to reproduce
Decode this bitstream:
[bit_sim.zip](/uploads/9d83c19b73adb3eb4d82eb90c45d8ea6/bit_sim.zip)
<!-- Commandline or script -->
```bash
./IVAS_cod_flt_ref -dtx -stereo 48000 48 stereo.wav bit
networkSimulator_g192 ../ivas-codec/scripts/dly_error_profiles/dly_error_profile_11.dat bit bit_sim trace 1 0
./IVAS_dec_fx -voip mono 16 bit_sim /dev/null
```
<!--- Below are labels that will be added but are not shown in description. This is a template to help fill them.
Add further information to the first row and remove and add labels as necessary. -->
issue