Convert CreateDC to unicode in the driver interface.

diff --git a/include/wingdi.h b/include/wingdi.h
index ef4f6f5..e60203a 100644
--- a/include/wingdi.h
+++ b/include/wingdi.h
@@ -3228,6 +3228,7 @@
 BOOL      WINAPI FloodFill(HDC,INT,INT,COLORREF);
 BOOL      WINAPI FrameRgn(HDC,HRGN,HBRUSH,INT,INT);
 BOOL      WINAPI GdiComment(HDC,UINT,const BYTE *);
+DEVMODEW * WINAPI GdiConvertToDevmodeW(const DEVMODEA *);
 BOOL      WINAPI GdiFlush(void);
 INT       WINAPI GetArcDirection(HDC);
 BOOL      WINAPI GetAspectRatioFilterEx(HDC,LPSIZE);