osxaudio: use GST_AUDIO_INFO_* accessors
osxaudio: use GST_AUDIO_INFO_* accessors

Changes include the following:

 * Update classname references
 * Replace GST_BOILERPLATE_FULL with G_DEFINE_TYPE
 * Use new GstAudioInfo struct and methods
 * Use new buffer memory allocation scheme

Conflicts:
	sys/osxaudio/gstosxaudioringbuffer.c

Distrotech/gst-plugins-good,Distrotech/gst-plugins-good,Distrotech/gst-plugins-good,Distrotech/gst-plugins-good,Distrotech/gst-plugins-good