harmonization of modif_fs
# Basic info
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- Float reference:
- Encoder (float):
- Decoder (float):
- Fixed point:
- Encoder (fixed): 244fba7c9
- Decoder (fixed): 244fba7c9
# Bug description
Most of modif_fs_fx and modif_fs_ivas_fx are the same, can easily be harmonized
# Ways to reproduce
Box folder: ...\\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\\issues\\issue-xxxx
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```bash
```
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issue