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Wrong ISM extended metadata decoding

There is a bug in the ISM extended metadata decoding, where the pitch index is decoded using the wrong number of bits.

The related code is at https://forge.3gpp.org/rep/sa4/audio/ivas-basop/-/blob/main/lib_dec/ivas_ism_metadata_dec.c?ref_type=heads#L1084:

yaw_fx = ism_dequant_meta_fx( idx_angle1, ism_azimuth_borders_fx, ISM_Q_STEP_FX, ISM_Q_STEP_BORDER_FX, ( 1 << ISM_AZIMUTH_NBITS ) );
#ifdef FIX
pitch_fx = ism_dequant_meta_fx( idx_angle2, ism_elevation_borders_fx, ISM_Q_STEP_FX, ISM_Q_STEP_BORDER_FX, ( 1 << ISM_ELEVATION_NBITS ) 
#else
pitch_fx = ism_dequant_meta_fx( idx_angle2, ism_elevation_borders_fx, ISM_Q_STEP_FX, ISM_Q_STEP_BORDER_FX, ( 1 << ISM_AZIMUTH_NBITS ) 
#endif);