BSE: bseconstvalues.hh: add constants for Wave chunk and cache limits
BSE: bseconstvalues.hh: add constants for Wave chunk and cache limits

* Limit file expansion and chunk caching to 64MB
* Limit support for multi-channel WaveChunks to 8 channels

Signed-off-by: Tim Janik <6ec6ff229c4e1c5bbd5933ee92e6c5832ff023bb@gnu.org>

swesterfeld/beast,swesterfeld/beast,swesterfeld/beast,swesterfeld/beast,swesterfeld/beast,tim-janik/beast,tim-janik/beast,tim-janik/beast,swesterfeld/beast,swesterfeld/beast,tim-janik/beast,tim-janik/beast,tim-janik/beast,tim-janik/beast