High MLD fixes, bug fixes and Q-info updates

[x] Fix for wrong q of exc buffers
[x] bug-fix in attack detection
[x] Removed saturations in find_enr_dft_fx and ivas_find_enr1
[x] Q documentation and Basop updation
[x] High mld fix for [basop_encoder-Multi-channel 7_1_4 bitrate switching from 13.2 kbps to 512 kbps, 48kHz in, 48kHz out, 7_1_4 out]
[x] Bug fix related to bckr