Make DirectX default on XP, instead of Direct3d

This is not manageable.
After the black screens, as reproduced by Rémi, (fixed I hope)
After the grey stripes, (fixed too, I think with DevCaps2)
There is still:
 - the yellow middle stripe, with failing IDirect3DDevice9::StretchRect
 - the subtitle blending issue, with absolutly no messages #6542

We have enough to do with the delayed pictures not displayed, in case of
subtitles and the broken audio in so many situations (not to mention the
volume delay...)

modules/video_output/msw/direct3d.c

@@ -143,6 +143,11 @@ static int Open(vlc_object_t *object)
     vout_display_t *vd = (vout_display_t *)object;
     vout_display_sys_t *sys;
 
+    OSVERSIONINFO winVer;
+    winVer.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
+    if(GetVersionEx(&winVer) && winVer.dwMajorVersion < 6 && !object->b_force)
+        return VLC_EGENERIC;
+
     /* Allocate structure */
     vd->sys = sys = calloc(1, sizeof(vout_display_sys_t));
     if (!sys)