[Bug 19160] Orly's Draw-A-Story demo crashes on startup (dmDriverExtra is not initialized)

https://bugs.winehq.org/show_bug.cgi?id=19160

--- Comment #8 from Dmitry Timoshkov  ---
(In reply to Dmitry Timoshkov from comment #7)
> Created attachment 52081 [details]
> patch
>
> Attached patch fixes particular crash in CreateDC16 due to huge (not
> initialized
> dmDriverExtra) field. Application still crashes, but in a different place.

It's worth to note that it's almost impossible to test whether it's correct
to modify dmDriverExtra in the application provided buffer, since the target
app is 16-bit and the test has to be 16-bit as well.