Interchangeability of fixed and floating-point functions is not available

Basic info

The formal requirements indicate that:

the goal is that the original functions could be used interchangeably during development; function names of converted functions shall avoid symbol clashes during the development

In the code, most of the fixed-point functions are kept under the IVAS_FLOAT_FIXED macro, while the floating-point functions are available with the IVAS_FLOAT_FIXED macro undefined. However, the code does not build with IVAS_FLOAT_FIXED undefined. There is no clear way of interchanging floating and fixed-point functions. It has been also found that the floating-point code is not complete anymore (e.g., set_base_config in ivas_reverb.c. Furthermore, many fixed-point functions don't have the _fx suffix in the function name.