hda: do not mix output and input streams, RHBZ #740493

Windows 7 may use the same stream number for input and output.
That will result in lot of garbage on playback.

The hardcoded value of 4 needs to be in sync with GCAP streams
description and IN/OUT registers.

Signed-off-by: Marc-Andr? Lureau <marcandre.lureau@redhat.com>
Signed-off-by: malc <av1474@comtv.ru>