illumos gate

This is a very old problem -- (surprisingly I couldn't find a reference to an open issue for it though.)

The audioens driver does not function when running as a guest in VMware - no output is emitted, and the audio "sample counter" never makes progress. It looks like a device hang to the end user.

The story here is that the emulated audio device isn't quite the same as real hardware -- in particular, the emulation relies on the user to pules an interrupt enable at fairly frequent rates in order to ensure that the audio emulation makes progress. So the "interrupt free" design in Boomer does not function.

The solution to this is to return interrupt based processing to the driver, but we can do that conditionally based on whether VMware is detected or not using get_hwenv(). Actually we should probably just do this for all virtual environments. (Note: I have not tested this on virtual box. I have no idea if audio even works there.)