[PATCH] include: Add xact3.h

[Vijay Kiran Kamuju]

v2 will be sent later this week without the changes for xact3wb.h,
after the patch for xact3wb.h is accepted.

On Mon, Mar 16, 2020 at 1:39 AM Vijay Kiran Kamuju <infyquest at gmail.com> wrote:
>
> Based on work by Ethan Lee and Alistair Leslie-Hughes
> Use the header file directly instead of idl file just like other
> directx headers like dsound.h
>
> Signed-off-by: Vijay Kiran Kamuju <infyquest at gmail.com>