Collection of fixes in EVS BASOP part

This issue is intended to collect bugs and possible CRs to EVS BASOP based on findings in the EVS part of the IVAS BASOP framework. Note that the list of FLP fixes or fixes to both FLP and BASOP can be found at ivas-codec-pc/ivas-codec#1062.

In general, don't implement fixes for EVS for now; possible exceptions, where it impacts the verification of IVAS code.

List of BASOP-only EVS issues:

• #1296 - potential bug in SWB-BWE excitation rescaling in DTX
• #1295 - bug in ACELP music post-processor
• #1294 - bug in ACELP 0-BWE memory reset
• struct dispMem_fx should be defined in stat_com.h and #include "stat_dec.h" should be removed from stat_enc.h
• #1432 (closed) - Difference in swb_tbe_enc_fx float and fixed-point code in EVS
• #1818 (closed) - wrong-pitch-initialization
• #2015 - scaling factor is not passed to the AVQ in higher-ACELP