soundcard.h expose device block size

[blubee blubeeme]

I'm looking at FreeBSD's soundcard.h and it doesn't seem to expose the
hardware block size, this seems like a limitation stemming from FreeBSD's
soundcard.h being an extension of OSS.

Since we've already implemented a lot of additional features on top of the
OSS API, is it possible to also expose the hardware block size for
applications that might need access to that information?

Best,
Owen