JBM: SPAR low rate smoothing factor calculation may use undefined values
### Basic info
- Commit SHA: 5924d993e3ab8572fa53626ac5bf31865e4c31f2
- Platform: all
### Bug description
The function `ivas_spar_calc_smooth_facs()` uses the constant `MAX_PARAM_SPATIAL_SUBFRAMES` to loop over the CLDFB time slots in a subframe. In the JBM case a subframe can have less CLDFB time slots than `MAX_PARAM_SPATIAL_SUBFRAMES`, so it will access undefined values in this case.
### Ways to reproduce
On Linux:
```
./IVAS_cod -sba 3 13200 48 scripts/testv/stv3OA48c.wav test.192
scripts/tools/Linux/networkSimulator_g192 scripts/dly_error_profiles/dly_error_profile_10.dat test.192 test_rtp.192 trace_out 1 0
/usr/bin/valgrind ./IVAS_dec -voip HOA3 48 test_rtp.192 test_rtp.dec.HOA3.wav
```
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issue