winealsa: Separate read and write pointers.

[Andrew Eikum]

On Mon, Dec 17, 2012 at 05:01:29PM +0100, Joerg-Cyril.Hoehle at t-systems.com wrote:
> Furthermore, this patch eases integration of my lock-less code, which
> I'll not release for now, by cleanly separating read and write
> pointers during playback and capture.  No more adding of two volatile
> entities moving in opposite directions!
> 

This seems to be the main goal of the patch. I tested it against my
usual set of applications both with and without PulseAudio.  This
patch seems fine to me.

I'll take a look at your lockless patch on bug 29531, and maybe we can
get that into Wine after the next release?

Andrew