Stereo Downmix EVS functions conversion, cleanup and encoder LTV crash fixes
[x] Stereo Downmix EVS functions conversion
[x] Fix for ltv crash issues: [ltv-MASA 1TC at 13.2 kbps, 48kHz in, 48kHz out, EXT out], [ltv-Multi-channel 5_1 at 13.2 kbps, 48kHz in, 48kHz out]-, [ltv-Multi-channel 5_1_4 at 48 kbps, 48kHz in, 48kHz out, BINAURAL_ROOM_IR out, HR]-, [ltv-Multi-channel 7_1_4 at 96 kbps, 48kHz in, 48kHz out, STEREO out], [ltv-Multi-channel 5_1_2 at 32 kbps, 48kHz in, 48kHz out, STEREO out, random FER at 5%], [ltv-Multi-channel 7_1_4 at 64 kbps, 48kHz in, 48kHz out, MONO out, random FER at 5%], [ltv-Multi-channel 7_1_4 at 96 kbps, 48kHz in, 48kHz out, 5_1 out, random FER at 5%], [ltv-Multi-channel 5_1 bitrate switching from 13.2 kbps to 512 kbps, 48kHz in, 48kHz out, 7_1_4 out], [ltv-Multi-channel 5_1_2 bitrate switching from 13.2 kbps to 512 kbps, 48kHz in, 16kHz out, BINAURAL_ROOM out], [ltv-Multi-channel 7_1_4 bitrate switching from 13.2 kbps to 512 kbps, 48kHz in, 48kHz out, BINAURAL out (Model from file)], [ltv-Multi-channel 7_1_4 bitrate switching from 13.2 kbps to 512 kbps, 48kHz in, 48kHz out, HOA3 out], [ltv-Multi-channel 7_1_4 bitrate switching from 24.4 kbps to 256 kbps, 48kHz in, 32kHz out, STEREO out, FER at 5%]
[x] ivas_core_pre_proc_front and pre_proc_ivas cleanup
[x] Q-info updates for decoder