audio/portaudio: Add three new functions* required by Audacity

• Pa_GetStreamHostApiType, PaOSS_GetStream{In,Out}putDevice

This will allow us to change audio/audacity to use audio/portaudio
instead of the bundled version. End goal is sndio support in
Audacity without having to duplicate existing patches.

While here

• Remove unnecessary patches
• Cleanup DOCS and PATEST install
• Take maintainership

Obtained from: Audacity 2.2.2's portaudio.patch