Decoder crash for McMASA 5.1 at 32kbps JBM decoding in ivas_fec_noise_filling_fx()
# Basic info
<!--- Add commit SHA used to reproduce -->
- Float reference:
- Encoder (float): ceb8871fb395dc677e0a02e8dba99d36074630c2
- Decoder (float):
- Fixed point:
- Encoder (fixed): d74de338b9d39268bf1db19b2c5792ca359ab02b
- Decoder (fixed):
# Bug description
The fixed point decoder crashes with an assert:
```
Assertion failed: (0), function L_shl, file basop32.c, line 2326.
```
{width=403 height=336}
# Ways to reproduce
Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-1437
<!-- Commandline or script -->
```bash
./IVAS_cod_flt_ref -mc 5_1 -max_band FB 32000 48 bm2aa1s04_48.10dB.wav bit
networkSimulator_g192 dly_error_profile_10.dat bit bit_sim trace 1 0
./IVAS_dec_fx -voip 5_1 16 bit_sim out.wav
```
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issue