Miniaudio

- Fix a possible deadlock when stopping devices.

- Core Audio: Fix some deadlock errors.

- Fix a bug when converting from stereo to mono.
- PulseAudio: Fix a glitch when pausing and resuming a device.

- Core Audio: Fix a deadlock when the default device is changed.
- Core Audio: Fix compilation errors on macOS and iOS.
- PulseAudio: Fix a bug where the stop callback is not fired when a device is unplugged.
- PulseAudio: Fix a null pointer dereference.

- Fix a linking error when MA_DEBUG_OUTPUT is not enabled.
- Fix an error where ma_log_postv() does not return a value.
- OpenSL: Fix a bug with setting of stream types and recording presets.

- Fix a bug with log message formatting.
- Fix build when compiling with MA_NO_THREADING.
- Minor updates to channel mapping.