[non-be] Add object editing gain limitations as agreed.
Limits gain editing internally as proposed in #1431
- For discrete: +12dB to -inf dB (0.0f linear)
- For parametric modes: +12dB to -24dB
Requested reviewer: @weckbecker
Edited by lintervo
Limits gain editing internally as proposed in #1431
Requested reviewer: @weckbecker