Improve WMOPS of dot_product_cholesky_fixed()

Basic info

in ivas_tools.c, the function dot_product_cholesky_fixed() is using the rather slow BASOP_Util_Add_Mant32Exp() function. It can be replaced with a 64 bit addition.

• Float reference:
  • Encoder (float):
  • Decoder (float):
• Fixed point:
  • Encoder (fixed):
  • Decoder (fixed):

Bug description

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-xxxx