Now, winealsa maintains its own buffer, which is written to ALSA on the
period cycle requested by the application. We also let ALSA start when
it has enough data and stop when it runs out, recovering from the
expected underruns. This seems to be more like how ALSA expects to be
used.

wined3d: Return WINED3DERR_NOTFOUND if the render target is NULL in wined3d_device_get_render_target().

This is similar to how wined3d_device_get_depth_stencil() works.