- Define new structure bx_pcm_param_t and use it as a parameter for the method
sendwavepacket(). The method startwavepacket() is now called from
sendwavepacket() in case of a parameter change (temporary solution).
- soundsdl: Replaced waveready() call by some more accurate code for buffer
space check in sendwavepacket().
- soundsdl: Moved code for reading from audio buffer to a new function.
- soundsdl: Temporarily increase the audio buffer size.
- Preparing the SB16 code for the OPL emulation port from DOSBox.
