Get rid of unnecessary cast

Parameter is already of HDC type so this cast is unnecessary and can be removed.

src/msw/utilsgui.cpp

@@ -206,7 +206,7 @@ void PixelToHIMETRIC(LONG *x, LONG *y)
 
 void wxDrawLine(HDC hdc, int x1, int y1, int x2, int y2)
 {
-    MoveToEx(hdc, x1, y1, NULL); LineTo((HDC) hdc, x2, y2);
+    MoveToEx(hdc, x1, y1, NULL); LineTo(hdc, x2, y2);
 }
 
 // Function dedicated to drawing horizontal/vertical lines with solid color