Add missing part from IVAS_DEC_GetEditableParameters and adjust to be in line with float version.

• Link to issue in BASOP repo: #2134 (closed)
• Link to original MR in float repo: ivas-codec-pc/ivas-codec!1915 (merged)
• Requested reviewers: @weckbecker @vaclav

This implements the missing parts for BASOP main. Slight differences to version in MR !2431 (merged) as variables are used differently.