flag_noisy_speech threshold mis-scaled (Q23 vs Q0)
# Basic info
<!--- Add commit SHA used to reproduce -->
- Fixed point:
- Decoder (fixed): 5440e481
# Bug description
In lib_dec/ivas_stereo_cng_dec_fx.c, the noisy-speech flag is computed as:
```bash
Word16 q_lp_noise = 0; // st->hFdCngDec->q_lp_noise; // to be populated appropriately.
...
flag_noisy_speech = extract_l( LT_32( L_shr( L_sub( lp_speech, lp_noise ), q_lp_noise ), 28 ) );
```
But lp_speech and lp_noise are Q23 dB values, so this compares a Q23 difference, against the integer 28, diverging from the float reference (lp_speech - lp_noise) < 28.f.
<!--- 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